W3C

PROV-N: The Provenance Notation

Final review before Last Call Vote (Diffs since last release)

W3C Editor's Draft 29 June 2012

This version:
http://dvcs.w3.org/hg/prov/raw-file/default/model/prov-n.html
Latest published version:
http://www.w3.org/TR/prov-n/
Latest editor's draft:
http://dvcs.w3.org/hg/prov/raw-file/default/model/prov-n.html
Previous version:
http://www.w3.org/TR/2012/WD-prov-n-20120503/
Editors:
Luc Moreau, University of Southampton
Paolo Missier, Newcastle University

Abstract

Provenance is information about entities, activities, and people involved in producing a piece of data or thing, which can be used to form assessments about its quality, reliability or trustworthiness. PROV-DM is the conceptual data model that forms a basis for the W3C provenance (PROV) family of specifications. PROV-DM distinguishes core structures, forming the essence of provenance information, from extended structures catering for more specific uses of provenance. PROV-DM is organized in six components, respectively dealing with: (1) entities and activities, and the time at which they were created, used, or ended; (2) derivations of entities from entities; (3) agents bearing responsibility for entities that were generated and activities that happened; (4) a notion of bundle, a mechanism to support provenance of provenance; and, (5) properties to link entities that refer to the same thing; (6) collections forming a logical structure for its members.

To provide examples of the PROV data model, the PROV notation (PROV-N) is introduced: aimed at human consumption, PROV-N allows serializations of PROV instances to be created in a compact manner. PROV-N facilitates the mapping of the PROV data model to concrete syntax, and is used as the basis for a formal semantics of PROV. The purpose of this document is to define the PROV-N notation.

Status of This Document

This section describes the status of this document at the time of its publication. Other documents may supersede this document. A list of current W3C publications and the latest revision of this technical report can be found in the W3C technical reports index at http://www.w3.org/TR/.

Intended to be Last Call (TBC)

This is the fifth public release of the PROV-DM document. Publication as Last Call working draft means that the Working Group believes that it has satisfied the relevant technical requirements outlined in its charter on this document. The design is not expected to change significantly, going forward, and now is the key time for external review, before the implementation phase.

This specification identifies one feature at risk: Mention might be removed from PROV if implementation experience reveals problems with supporting this construct.

Please Comment By 2012-09-13 (TBC)

The PROV Working group seeks public feedback on this Working Draft. The end date of the Last Call review period is 2012-09-13 (TBC), and we would appreciate comments by that date to [email protected]

PROV Family of Specifications

This document is part of the PROV family of specifications, a set of specifications defining various aspects that are necessary to achieve the vision of inter-operable interchange of provenance information in heterogeneous environments such as the Web. The specifications are:

How to read the PROV Family of Specifications

This document was published by the Provenance Working Group as an Editor's Draft. If you wish to make comments regarding this document, please send them to [email protected] (subscribe, archives). All feedback is welcome.

Publication as an Editor's Draft does not imply endorsement by the W3C Membership. This is a draft document and may be updated, replaced or obsoleted by other documents at any time. It is inappropriate to cite this document as other than work in progress.

This document was produced by a group operating under the 5 February 2004 W3C Patent Policy. W3C maintains a public list of any patent disclosures made in connection with the deliverables of the group; that page also includes instructions for disclosing a patent. An individual who has actual knowledge of a patent which the individual believes contains Essential Claim(s) must disclose the information in accordance with section 6 of the W3C Patent Policy.

Table of Contents

1. Introduction

Provenance is a record that describes the people, institutions, entities, and activities, involved in producing, influencing, or delivering a piece of data or a thing in the world. Two companion specifications respectively define PROV-DM, a data model for provenance, allowing provenance descriptions to be expressed [PROV-DM] and a set of constraints that provenance descriptions are expected to satisfy [PROV-CONSTRAINTS].

1.1 Purpose of this Document and target audience

A key goal of PROV is the specification of a machine-processable data model for provenance. However, communicating provenance between humans is also important when teaching, illustrating, formalizing, and discussing provenance-related issues. With these two requirements in mind, this document introduces PROV-N, a syntax notation designed to write instances of the PROV data model according to the following design principles: PROV-N has several known uses:

This document introduces the PROV-N grammar along with examples of its usage.

Its target audience is twofold:

1.2 Structure of this Document

This document structured as follows.

Section 2 provides general consideration about the PROV-N grammar.

Section 3 presents the grammar of all expressions of the language grouped according to the PROV data model components.

Section 4 defines the grammar of toplevel bundles, a house-keeping construct of PROV-N capable of packaging up PROV-N expressions and namespace declarations.

Section 5 defines media type for the PROV-N notation.

1.3 Notational Conventions

The key words "must", "must not", "required", "shall", "shall not", "should", "should not", "recommended", "may", and "optional" in this document are to be interpreted as described in [RFC2119].

The following namespaces prefixes are used throughout this document.

Table 1: Prefix and Namespaces used in this specification
prefixnamespace uri definition
provhttp://www.w3.org/ns/prov#The PROV namespace (see Section 4.7.1)
xsdhttp://www.w3.org/2000/10/XMLSchema#XML Schema Namespace [XMLSCHEMA11-2]
(others)(various)All other namespace prefixes are used in examples only.
In particular, URIs starting with "http://example.com" represent
some application-dependent URI [URI]

2. General grammar considerations

2.1 Functional-style Syntax

PROV-N adopts a functional-style syntax consisting of a predicate name and an ordered list of terms. All PROV data model relations involve two primary elements, the subject and the object, in this order. Furthermore, some expressions also admit additional elements that further characterize it.

The following expression should be read as "e2 was derived from e1". Here e2 is the subject, and e1 is the object.
wasDerivedFrom(e2, e1)
In the following expressions, the optional activity a along with the generation and usage identifiers g2 and u1:
wasDerivedFrom(e2, e1, a, g2, u1)

2.2 EBNF Grammar

The grammar is specified using the Extended Backus-Naur Form (EBNF) notation.

Each production rule (or production, for short) in the grammar defines one non-terminal symbol E, in the following form:

E ::= term

Within the term on the right-hand side of a rule, the following terms are used to match strings of one or more characters:

  • E: matches term satisfying rule for symbol E.
  • abc: matches the literal string inside the single quotes.
  • term: optional term, matches term or nothing.
  • term: matches one or more occurrences of term.
  • term: matches zero or more occurrences of term.
  • term | term: matches one of the two terms.
The grammar is centered on nonterminals for various types of expression. The main production is introduced here below as it reflects the rationale for the design of the entire grammar. Note that parser developers may use the top level bundle nonterminal as a starting point instead.
[2]    expression    ::=    ( entityExpression | activityExpression | generationExpression | usageExpression | startExpression | endExpression | invalidationExpression | communicationExpression | agentExpression | associationExpression | attributionExpression | delegationExpression | derivationExpression | influenceExpression | alternateExpression | specializationExpression | mentionExpression | membershipExpression )
Each expression non-terminal expression, i.e., entityExpression, activityExpression etc., corresponds to one element (entity, activity, etc.) of the PROV data model.

A PROV-N document consists of a collection of expressions, wrapped in a toplevel bundle with some namespace declarations, such that the text for an element matches the corresponding expression production of the grammar.

2.3 Optional terms in expressions

Some terms in an expression may be optional. For example:
wasDerivedFrom(e2, e1, a, g2, u1)
wasDerivedFrom(e2, e1)
In a derivation expression, the activity, generation, and usage are optional terms. They are specified in the first derivation, but not in the second.
activity(a2, 2011-11-16T16:00:00, 2011-11-16T16:00:01)
activity(a1)
The start and end times for Activity a1 are optional. They are specified in the first expression, but not in the second.

The general rule for optionals is that, if none of the optionals are used in the expression, then they are simply omitted, resulting in a simpler expression as in the examples above.

However, it may be the case that only some of the optional terms are omitted. Because the position of the terms in the expression matters, an additional marker must be used to indicate that a particular term is not available. The symbol '-' is used for this purpose.

In the first expression below, all optionals are specified. However in the second and third, only one optional is specified, forcing the use of the marker for the missing terms.

wasDerivedFrom(e2, e1, a, g2, u1)
wasDerivedFrom(e2, e1, -, -, u1)
wasDerivedFrom(e2, e1, a, -, -)
Note that the more succinct form is just shorthand for a complete expression with all the markers specified:
activity(a1)
activity(a1, -, -)

2.4 Identifiers and attributes

Most expressions defined in the grammar include the use of two terms: an identifier and a set of attribute-value pairs, delimited by square brackets. Identifiers are optional except for Entities, Activites, and Agents. Identifiers are always the first term in any expression. By convention, optional identifiers are separated using a semi-colon ';'. This makes it possible to completely omit an optional identifier with no ambiguity arising. Also, if the set of attribute-value pairs is present, it is always the last term in any expression.

Derivation has an optional identifier. In the first expression, the identifier is not available, while it is explicit in the second. The third example shows that one can optionally indicate the missing identifier using the - marker.

wasDerivedFrom(e2, e1)
wasDerivedFrom(d; e2, e1)
wasDerivedFrom(-; e2, e1)
Lack of attributes can be equivalently expressed by omitting the list, or by using an empty list.

The first and second activities have no attributes. The third activity has two attributes.

activity(ex:a10)
activity(ex:a10, [])
activity(ex:a10, [ex:param1="a", ex:param2="b"])

2.5 Comments

Comments in PROV-N take two forms:

Comments are treated as white space.

3. PROV-N Productions per Component

This section introduces grammar productions for each expression, followed by small examples of expressions illustrating the grammar. Strings conforming to the grammar are valid expressions in the PROV-N language.

3.1 Component 1: Entities and Activities

3.1.1 Entity

[3]    entityExpression    ::=    "entity" "(" identifier optionalAttributeValuePairs ")"
[4]    optionalAttributeValuePairs    ::=    ( "," "[" attributeValuePairs "]" )?
[5]    attributeValuePairs    ::=    ( | attributeValuePair ( "," attributeValuePair )* )
[6]    attributeValuePair    ::=    attribute "=" literal

The following table summarizes how each constituent of a PROV-DM Entity maps to a non-terminal.

EntityNon-Terminal
ididentifier
attributesoptionalAttributeValuePairs
entity(tr:WD-prov-dm-20111215, [ prov:type="document" ])
Here tr:WD-prov-dm-20111215 is the entity identifier, and [ prov:type="document" ] groups the optional attributes, only one in this example, with their values.

entity(tr:WD-prov-dm-20111215)
Here, the optional attributes are absent.

3.1.2 Activity

[7]    activityExpression    ::=    "activity" "(" identifier ( "," timeOrMarker "," timeOrMarker )? optionalAttributeValuePairs ")"
[8]    timeOrMarker    ::=    ( time | "-" )

The following table summarizes how each constituent of a PROV-DM Activity maps to a non-terminal.

ActivityNon-Terminal
ididentifier
startTimetimeOrMarker
endTimetimeOrMarker
attributesoptionalAttributeValuePairs
activity(ex:a10, 2011-11-16T16:00:00, 2011-11-16T16:00:01, [prov:type="createFile"])

Here ex:a10 is the activity identifier, 2011-11-16T16:00:00 and 2011-11-16T16:00:01 are the optional start and end times for the activity, and [prov:type="createFile"] are optional attributes.

The remaining examples show cases where some of the optionals are omitted.
activity(ex:a10)
activity(ex:a10, -, -)
activity(ex:a10, -, -, [prov:type="edit"])
activity(ex:a10, -, 2011-11-16T16:00:00)
activity(ex:a10, 2011-11-16T16:00:00, -)
activity(ex:a10, 2011-11-16T16:00:00, -, [prov:type="createFile"])
activity(ex:a10, [prov:type="edit"])

3.1.3 Generation

[9]    generationExpression    ::=    "wasGeneratedBy" "(" optionalIdentifier eIdentifier ( "," aIdentifierOrMarker "," timeOrMarker )? optionalAttributeValuePairs ")"
[10]    optionalIdentifier    ::=    ( identifierOrMarker ";" )?
[11]    identifierOrMarker    ::=    ( identifier | "-" )

The following table summarizes how each constituent of a PROV-DM Generation maps to a non-terminal.

GenerationNon-Terminal
idoptionalIdentifier
entityeIdentifier
activityaIdentifierOrMarker
timetimeOrMarker
attributesoptionalAttributeValuePairs
wasGeneratedBy(ex:g1; tr:WD-prov-dm-20111215, ex:edit1, 2011-11-16T16:00:00,  [ex:fct="save"])

Here ex:g1 is the optional generation identifier, tr:WD-prov-dm-20111215 is the identifier of the entity being generated, ex:edit1 is the optional identifier of the generating activity, 2011-11-16T16:00:00 is the optional generation time, and [ex:fct="save"] are optional attributes.

The remaining examples show cases where some of the optionals are omitted.
wasGeneratedBy(e2, a1, tr:WD-prov-dm-20111215)
wasGeneratedBy(e, ex:edit1, 2011-11-16T16:00:00)
wasGeneratedBy(e2, a1, -, [ex:fct="save"])     
wasGeneratedBy(e2, [ex:fct="save"])     
wasGeneratedBy(ex:g1; e)
wasGeneratedBy(ex:g1; e, a, tr:WD-prov-dm-20111215)

Even though the production generationExpression allows for expressions wasGeneratedBy(e2, -, -) and wasGeneratedBy(-; e2, -, -), these expressions are not valid in PROV-N, since at least one of id, activity, time, and attributes must be present.

3.1.4 Usage

[12]    usageExpression    ::=    "used" "(" optionalIdentifier aIdentifier "," ( "," eIdentifierOrMarker "," timeOrMarker )? optionalAttributeValuePairs ")"

The following table summarizes how each constituent of a PROV-DM Usage maps to a non-terminal.

UsageNon-Terminal
idoptionalIdentifier
activityaIdentifier
entityeIdentifierOrMarker
timetimeOrMarker
attributesoptionalAttributeValuePairs
used(ex:u1; ex:act2, ar3:0111, 2011-11-16T16:00:00, [ex:fct="load"])
 

Here ex:u1 is the optional usage identifier, ex:act2 is the identifier of the using activity, ar3:0111 is the identifier of the entity being used, 2011-11-16T16:00:00 is the optional usage time, and [ex:fct="load"] are optional attributes.

The remaining examples show cases where some of the optionals are omitted.
used(ex:act2)
used(ex:act2, ar3:0111, 2011-11-16T16:00:00)
used(a1,e1, -, [ex:fct="load"])
used(ex:u1; ex:act2, ar3:0111, -)

Even though the production usageExpression allows for expressions used(a2, -, -) and used(-; e2, -, -), these expressions are not valid in PROV-N, since at least one of id, entity, time, and attributes must be present.

3.1.5 Communication

[13]    communicationExpression    ::=    "wasInformedBy" "(" optionalIdentifier aIdentifier "," aIdentifier optionalAttributeValuePairs ")"

The following table summarizes how each constituent of a PROV-DM Communication maps to a non-terminal.

CommunicationNon-Terminal
idoptionalIdentifier
informedaIdentifier
informantaIdentifier
attributesoptionalAttributeValuePairs
wasInformedBy(ex:inf1; ex:a1, ex:a2, [ex:param1="a", ex:param2="b"])

Here ex:inf1 is the optional communication identifier, ex:a1 is the identifier of the informed activity, ex:a2 is the identifier of the informant activity, and [ex:param1="a", ex:param2="b"] are optional attributes.

The remaining examples show cases where some of the optionals are omitted.
wasInformedBy(ex:a1, ex:a2)
wasInformedBy(ex:a1, ex:a2, [ex:param1="a", ex:param2="b"])
wasInformedBy(i; ex:a1, ex:a2)
wasInformedBy(i; ex:a1, ex:a2, [ex:param1="a", ex:param2="b"])

3.1.6 Start

[14]    startExpression    ::=    "wasStartedBy" "(" optionalIdentifier aIdentifier ( "," eIdentifierOrMarker "," aIdentifierOrMarker "," timeOrMarker )? optionalAttributeValuePairs ")"

The following table summarizes how each constituent of a PROV-DM Start maps to a non-terminal.

StartNon-Terminal
idoptionalIdentifier
activityaIdentifier
triggereIdentifierOrMarker
starteraIdentifierOrMarker
timetimeOrMarker
attributesoptionalAttributeValuePairs
wasStartedBy(s; ex:act2, ex:trigger, ex:act1, 2011-11-16T16:00:00, [ex:param="a"])
  

Here s is the optional start identifier, ex:act2 is the identifier of the started activity, ex:trigger is the optional identifier for the entity that triggered the activity start, ex:act1 is the optional identifier for the activity that generated the (possibly unspecified) entity ex:trigger, 2011-11-16T16:00:00 is the optional start time, and [ex:param="a"] are optional attributes.

The remaining examples show cases where some of the optionals are omitted.
wasStartedBy(ex:act2, -, ex:act1, -)
wasStartedBy(ex:act2, -, ex:act1, 2011-11-16T16:00:00)
wasStartedBy(ex:act2, -, -, 2011-11-16T16:00:00)
wasStartedBy(ex:act2, [ex:param="a"])
wasStartedBy(s; ex:act2, e, ex:act1, 2011-11-16T16:00:00)

Note: Even though the production startExpression allows for expressions wasStartedBy(e2, -, -) and wasStartedBy(-; e2, -, -), these expressions are not valid in PROV-N, since at least one of id, trigger, starter, time, and attributes must be present.

3.1.7 End

[15]    endExpression    ::=    "wasEndedBy" "(" optionalIdentifier aIdentifier ( "," eIdentifierOrMarker "," aIdentifierOrMarker "," timeOrMarker )? optionalAttributeValuePairs ")"

The following table summarizes how each constituent of a PROV-DM End maps to a non-terminal.

EndNon-Terminal
idoptionalIdentifier
activityaIdentifier
triggereIdentifierOrMarker
enderaIdentifierOrMarker
timetimeOrMarker
attributesoptionalAttributeValuePairs
wasEndedBy(s; ex:act2, ex:trigger,ex:act3,  2011-11-16T16:00:00, [ex:param="a"])
  

Here s is the optional start identifier, ex:act2 is the identifier of the ending activity, ex:trigger is the identifier of the entity that triggered the activity end, ex:act3 is the optional identifier for the activity that generated the (possibly unspecified) entity e, 2011-11-16T16:00:00 is the optional usage time, and [ex:param="a"] are optional attributes.

The remaining examples show cases where some of the optionals are omitted.
wasEndedBy(ex:act2, ex:trigger, -, -)
wasEndedBy(ex:act2, ex:trigger, -, 2011-11-16T16:00:00)
wasEndedBy(ex:act2, -, -, 2011-11-16T16:00:00)
wasEndedBy(ex:act2, -, -, 2011-11-16T16:00:00, [ex:param="a"])
wasEndedBy(e; ex:act2)
wasEndedBy(e; ex:act2, ex:trigger, -, 2011-11-16T16:00:00)

Note:Even though the production endExpression allows for expressions wasEndedBy(e2, -, -) and wasEndedBy(-; e2, -, -), these expressions are not valid in PROV-N, since at least one of id, trigger, ender, time, and attributes must be present.

3.1.8 Invalidation

[16]    invalidationExpression    ::=    "wasInvalidatedBy" "(" optionalIdentifier eIdentifier ( "," aIdentifierOrMarker "," timeOrMarker )? optionalAttributeValuePairs ")"

The following table summarizes how each constituent of a PROV-DM Invalidation maps to a non-terminal.

InvalidationNon-Terminal
idoptionalIdentifier
entityeIdentifier
activityaIdentifierOrMarker
timetimeOrMarker
attributesoptionalAttributeValuePairs
wasInvalidatedBy(ex:i1; tr:WD-prov-dm-20111215, ex:edit1, 2011-11-16T16:00:00,  [ex:fct="save"])

Here ex:i1 is the optional invalidation identifier, tr:WD-prov-dm-20111215 is the identifier of the entity being invalidated, ex:edit1 is the optional identifier of the invalidating activity, 2011-11-16T16:00:00 is the optional invalidation time, and [ex:fct="save"] are optional attributes.

The remaining examples show cases where some of the optionals are omitted.
wasInvalidatedBy(tr:WD-prov-dm-20111215, ex:edit1, -)
wasInvalidatedBy(tr:WD-prov-dm-20111215, ex:edit1, 2011-11-16T16:00:00)
wasInvalidatedBy(e2, a1, -, [ex:fct="save"])     
wasInvalidatedBy(e2, -, -, [ex:fct="save"])     
wasInvalidatedBy(ex:i1; tr:WD-prov-dm-20111215, ex:edit1, -)
wasInvalidatedBy(tr:WD-prov-dm-20111215, ex:edit1, -)

Even though the production invalidationExpression allows for expressions wasInvalidatedBy(e2, -, -) and wasInvalidatedBy(-; e2, -, -), these expressions are not valid in PROV-N, since since at least one of id, activity, time, and attributes must be present.

3.2 Component 2: Derivations

3.2.1 Derivation

[17]    derivationExpression    ::=    "wasDerivedFrom" "(" optionalIdentifier eIdentifier "," eIdentifier ( "," aIdentifierOrMarker "," gIdentifierOrMarker "," uIdentifierOrMarker )? optionalAttributeValuePairs ")"

The following table summarizes how each constituent of a PROV-DM Derivation maps to a non-terminal.

DerivationNon-Terminal
idoptionalIdentifier
generatedEntityeIdentifier
usedEntityeIdentifier
activityaIdentifierOrMarker
generationgIdentifierOrMarker
usageuIdentifierOrMarker
attributesoptionalAttributeValuePairs
wasDerivedFrom(d, e2, e1, a, g2, u1, [ex:comment="a righteous derivation"])
  

Here d is the optional derivation identifier, e2 is the identifier for the entity being derived, e1 is the identifier of the entity from which e2 is derived, a is the optional identifier of the activity which used/generated the entities, g2 is the optional identifier of the generation, u1 is the optional identifier of the usage, and [ex:comment="a righteous derivation"] are optional attributes.

The remaining examples show cases where some of the optionals are omitted.
wasDerivedFrom(e2, e1)
wasDerivedFrom(e2, e1, a, g2, u1)
wasDerivedFrom(e2, e1, -, g2, u1)
wasDerivedFrom(e2, e1, a, -, u1)
wasDerivedFrom(e2, e1, a, g2, -)
wasDerivedFrom(e2, e1, a, -, -)
wasDerivedFrom(e2, e1, -, -, u1)
wasDerivedFrom(e2, e1, -, -, -)
wasDerivedFrom(d, e2, e1, a, g2, u1)
wasDerivedFrom(-, e2, e1, a, g2, u1)

3.2.2 Revision

wasDerivedFrom(d; e2, e1, a, g2, u1, 
               [prov:type='prov:Revision', 
                ex:comment="a righteous derivation"])
  

Here, the derivation from Example 17 is extended with a prov:type attribute and value prov:Revision.

3.2.3 Quotation

wasDerivedFrom(quoteId1; ex:blockQuote,ex:blog, ex:act1, ex:g, ex:u,
               [ prov:type='prov:Quotation' ])
  

Here, the derivation is provided with a prov:type attribute and value prov:Quotation.

3.2.4 Primary Source

wasDerivedFrom(src1;  ex:e1, ex:e2, ex:act, ex:g, ex:u, 
               [ prove:type='prov:PrimarySource' ])

Here, the derivation is provided with a prov:type attribute and value prov:PrimarySource.

3.3 Component 3: Agents, Responsibility, and Influence

3.3.1 Agent

[18]    agentExpression    ::=    "agent" "(" identifier optionalAttributeValuePairs ")"

The following table summarizes how each constituent of a PROV-DM Agent maps to a non-terminal.

AgentNon-Terminal
ididentifier
attributesoptionalAttributeValuePairs
agent(ag4, [ prov:type="prov:Person", ex:name="David" ])

Here ag is the agent identifier, and [ prov:type="prov:Person", ex:name="David" ] are optional attributes.

In the next example, the optional attributes are omitted.
agent(ag4)

3.3.2 Attribution

[19]    attributionExpression    ::=    "wasAttributedTo" "(" optionalIdentifier eIdentifier "," agIdentifier optionalAttributeValuePairs ")"

The following table summarizes how each constituent of a PROV-DM Attribution maps to a non-terminal.

AttributionNon-Terminal
idoptionalIdentifier
entityeIdentifier
agentagIdentifier
attributesoptionalAttributeValuePairs
wasAttributedTo(id; e, ag, [ex:license='cc:attributionURL' ])
  

Here id is the optional attribution identifier, e is an entity identifier, ag is the identifier of the agent to whom the entity is abscribed, and [ex:license='cc:attributionURL' ] are optional attributes.

The remaining examples show cases where some of the optionals are omitted.
wasAttributedTo(e, ag)
wasAttributedTo(e, ag, [ex:license='cc:attributionURL' ])

3.3.3 Association

[20]    associationExpression    ::=    "wasAssociatedWith" "(" optionalIdentifier aIdentifier "," agIdentifierOrMarker ( "," eIdentifierOrMarker )? optionalAttributeValuePairs ")"

The following table summarizes how each constituent of a PROV-DM Association maps to a non-terminal.

AssociationNon-Terminal
idoptionalIdentifier
activityaIdentifier
agentagIdentifierOrMarker
planeIdentifierOrMarker
attributesoptionalAttributeValuePairs
wasAssociatedWith(ex:agas; ex:a1, ex:ag1, ex:e1, [ex:param1="a", ex:param2="b"])
  

Here ex:agas is the optional attribution identifier, ex:a1 is an activity identifier, ex:ag1 is the optional identifier of the agent associated to the activity, ex:e1 is the optional identifier of the plan used by the agent in the context of the activity, and [ex:param1="a", ex:param2="b"] are optional attributes.

The remaining examples show cases where some of the optionals are omitted.
wasAssociatedWith(ex:a1, -, ex:e1)
wasAssociatedWith(ex:a1, ex:ag1)
wasAssociatedWith(ex:a1, ex:ag1, ex:e1)
wasAssociatedWith(ex:a1, ex:ag1, ex:e1, [ex:param1="a", ex:param2="b"])
wasAssociatedWith(a; ex:a1, -, ex:e1)

Note:The production associationExpression allows for expressions wasAssociatedWith(a, -, -) and wasAssociatiedWith(-; a, -, -). However, these expressions are not valid in PROV-N, since at least one of id, agent, plan, and attributes must be present.

3.3.4 Delegation

[21]    delegationExpression    ::=    "actedOnBehalfOf" "(" optionalIdentifier agIdentifier "," agIdentifier ( "," aIdentifierOrMarker )? optionalAttributeValuePairs ")"

The following table summarizes how each constituent of a PROV-DM Delegation maps to a non-terminal.

DelegationNon-Terminal
idoptionalIdentifier
delegateagIdentifier
responsibleagIdentifier
activityaIdentifierOrMarker
attributesoptionalAttributeValuePairs
actedOnBehalfOf(del1; ag2, ag1, a, [prov:type="contract"])
  

Here del1 is the optional delegation identifier, ag2 is the identifier for the delegate agent, ag1 is the identifier of the responsible agent, a is the optional identifier of the activity for which the delegation link holds, and [prov:type="contract"] are optional attributes.

The remaining examples show cases where some of the optionals are omitted.
actedOnBehalfOf(ag1, ag2)
actedOnBehalfOf(ag1, ag2, a)
actedOnBehalfOf(ag1, ag2, -, [prov:type="delegation"])
actedOnBehalfOf(ag2, ag3, a, [prov:type="contract"])
actedOnBehalfOf(r; ag2, ag3, a, [prov:type="contract"])

3.3.5 Influence

[22]    influenceExpression    ::=    "influence" "(" optionalIdentifier eIdentifier "," eIdentifier optionalAttributeValuePairs ")"

The following table summarizes how each constituent of a PROV-DM Influence maps to a non-terminal.

InfluenceNon-Terminal
idoptionalIdentifier
influenceeeIdentifier
influencereIdentifier
attributesoptionalAttributeValuePairs
influence(id,e2,e1,[ex:param="a"])
  

Here id is the optional influence identifier, e2 is an entity identifier, e1 is the identifier for an ancestor entity that e2 depends on, and [ex:param="a"] is the optional set of attributes.

The remaining examples show cases where some of the optionals are omitted.
influence(e2,e1)
influence(e2,e1,[ex:param="a"])
influence(id; e2,e1)

3.4 Component 4: Bundles

3.4.1 Bundle Declaration

[23]    namedBundle    ::=    "bundle" identifier (namespaceDeclarations)? (expression)* "endBundle"
bundle ex:author-view
  agent(ex:Paolo,   [ prov:type='prov:Person' ])
  agent(ex:Simon,   [ prov:type='prov:Person' ])
  ...
endBundle
  

Here ex:author-view is the name of the bundle.

3.5 Component 5: Alternate Entities

3.5.1 Alternate

[24]    alternateExpression    ::=    "alternateOf" "(" eIdentifier "," eIdentifier ")"

The following table summarizes how each constituent of a PROV-DM Alternate maps to a non-terminal.

AlternateNon-Terminal
alternate1eIdentifier
alternate2eIdentifier
alternateOf(tr:WD-prov-dm-20111215,ex:alternate-20111215)
Here tr:WD-prov-dm-20111215 is alternate for ex:alternate-20111215.

3.5.2 Specialization

[25]    specializationExpression    ::=    "specializationOf" "(" eIdentifier "," eIdentifier ")"

The following table summarizes how each constituent of a PROV-DM Specialization maps to a non-terminal.

SpecializationNon-Terminal
specificEntityeIdentifier
generalEntityeIdentifier
specializationOf(tr:WD-prov-dm-20111215,tr:prov-dm)
Here tr:WD-prov-dm-20111215 is a specialization of tr:prov-dm.

3.5.3 Mention

Note: This feature is "at risk" and may be removed from this specification based on feedback. Please send feedback to [email protected]

The expression Mention might be removed from PROV if implementation experience reveals problems with supporting this construct.

[26]    mentionExpression    ::=    "mentionOf" "(" identifier "," identifier "," bIdentifier ")"

The following table summarizes how each constituent of a PROV-DM Mention maps to a non-terminal.

MentionNon-Terminal
specificEntityeIdentifier
generalEntityeIdentifier
bundlebIdentifier
  mention(ex:report1_as_in_b1, ex:report1, ex:b1)   

Here ex:report1_as_in_b1 is an entity identifier, ex:report1 is an entity identifier, ex:b1 is the identifier for a bundle

3.6 Component 6: Collections

3.6.1 Membership

[27]    membershipExpression    ::=    "memberOf" "(" optionalIdentifier cIdentifier "," entitySet complete optionalAttributeValuePairs ")"
[28]    complete    ::=    ( "," ( "true" | "false" | "-" ) )?
[29]    entitySet    ::=    "{" (eIdentifier)* "}"

The following table summarizes how each constituent of a PROV-DM Membership maps to a non-terminal.

Collection MembershipNon-Terminal
idoptionalIdentifier
collectioncIdentifier
entity-setentitySet
completecomplete
attributesoptionalAttributeValuePairs
   memberOf(mId, c, {e1, e2, e3}, [])   // Collection membership
  

Here mId is the optional membership identifier, c is the identifier for the collection whose membership is stated, {e1, e2, e3} is the entity-set indicating the members of c, and [] is the optional (empty) set of attributes.

In the remaining examples, some of the optionals are omitted.
memberOf(c3, {e1})
memberOf(c3, {e1,e2})     // default "complete" flag is false
memberOf(c3, {e1,e2}, false)
memberOf(c3, {e1,e2}, true)
memberOf(c3, ,[])  
memberOf(c3, ,true, [])  

3.7 Further Expressions

This section defines further expressions of PROV-N.

3.7.1 Identifier

Various kinds of identifiers are used in productions.

[30]    eIdentifier    ::=    identifier
[31]    aIdentifier    ::=    identifier
[32]    agIdentifier    ::=    identifier
[33]    gIdentifier    ::=    identifier
[34]    uIdentifier    ::=    identifier
[36]    cIdentifier    ::=    identifier
[35]    dIdentifier    ::=    identifier
[37]    bIdentifier    ::=    identifier
[38]    eIdentifierOrMarker    ::=    ( eIdentifier | "-" )
[39]    aIdentifierOrMarker    ::=    ( aIdentifier | "-" )
[40]    agIdentifierOrMarker    ::=    ( agIdentifier | "-" )
[41]    gIdentifierOrMarker    ::=    ( gIdentifier | "-" )
[42]    uIdentifierOrMarker    ::=    ( uIdentifier | "-" )
[43]    identifier    ::=    QUALIFIED_NAME

A qualified name is a name subject to namespace interpretation. It consists of a namespace, denoted by an optional prefix, and a local name. The PROV data model stipulates that a qualified name can be mapped into an IRI by concatenating the IRI associated with the prefix and the local part.

A qualified name's prefix is optional. If a prefix occurs in a qualified name, it refers to a namespace declared in a namespace declaration. In the absence of prefix, the qualified name refers to the default namespace.

A PROV qualified name QUALIFIED_NAME has a more permissive syntax then XML's QName [XML-NAMES] and SPARQL PrefixedName [RDF-SPARQL-QUERY]. It is a PROV requirement that the concatenation of the namespace with the local part results in a valid IRI [IRI]. Given that ',' (comma), ';' (semi-colon), '=' (equal), '(' (left bracket), ')' (right bracket), '[' (left square bracket), ']' (right square bracket) are used by the PROV notation as delimiters, they are not allowed in local parts. Instead, they can be %-escaped or incorporated in the IRI denoted by a prefix.

Qualified names QUALIFIED_NAME consist of a prefix and a local part. Prefixes follow the production PN_PREFIX defined by SPARQL [RDF-SPARQL-QUERY]. Local parts have to be conformant with PN_LOCAL, which extends the original SPARQL PN_LOCAL definition by allowing further characters and %-escaped charaters (see PN_CHARS_OTHERS).

[59]    <QUALIFIED_NAME>    ::=    ( PN_PREFIX ":" )? PN_LOCAL
| PN_PREFIX ":"
[60]    <PN_LOCAL>    ::=    ( PN_CHARS_U | [0-9] | PN_CHARS_OTHERS ) ( ( PN_CHARS | "." | PN_CHARS_OTHERS )* ( PN_CHARS | PN_CHARS_OTHERS ) )?
[61]    <PN_CHARS_OTHERS>    ::=    PERCENT
| "/"
| "@"
| "~"
| "&"
| "+"
| "?"
| "#"
| "$"
[62]    <PERCENT>    ::=    "%" HEX HEX
[63]    <HEX>    ::=    [0-9]
| [A-F]
| [a-f]

Examples of articles on the BBC Web site seen as entities.

bundle
  prefix bbc <http://www.bbc.co.uk/>
  prefix bbcNews <http://www.bbc.co.uk/news/>

  entity(bbc:)                          // bbc site itself
  entity(bbc:news/)                     // bbc news
  entity(bbc:news/world-asia-17507976)  // a given news article

  entity(bbcNews:)                      // an alternative way of referring to the bbc news site

endBundle

Examples of entities with declared and default namespace.

bundle
  default <http://example.org/2/>
  prefix ex <http://example.org/1/>

  entity(ex:a)     //  corresponds to IRI http://example.org/1/a
  entity(ex:a/)    //  corresponds to IRI http://example.org/1/a/
  entity(ex:a/b)   //  corresponds to IRI http://example.org/1/a/b
  entity(b)        //  corresponds to IRI http://example.org/2/b
  entity(ex:1234)  //  corresponds to IRI http://example.org/2/1234
  entity(4567)     //  corresponds to IRI http://example.org/2/4567
endBundle

Note:The productions for qualifiedName and prefix are conflicting. In the context of a namespaceDeclaration, a parser should give precedence to the production for prefix.

3.7.2 Attribute

[44]    attribute    ::=    QUALIFIED_NAME

The reserved attributes in the PROV namespace are the following.

  1. prov:label
  2. prov:location
  3. prov:role
  4. prov:type
  5. prov:value

3.7.3 Literal

[45]    literal    ::=    typedLiteral
| convenienceNotation
[46]    typedLiteral    ::=    STRING_LITERAL "%%" datatype
[47]    datatype    ::=    QUALIFIED_NAME
[48]    convenienceNotation    ::=    STRING_LITERAL (LANGTAG)?
| INT_LITERAL
| QUALIFIED_NAME_LITERAL
[64]    <STRING_LITERAL>    ::=    STRING_LITERAL2
| STRING_LITERAL_LONG2
[66]    <INT_LITERAL>    ::=    ("-")? (DIGIT)+
[67]    <QUALIFIED_NAME_LITERAL>    ::=    "'" QUALIFIED_NAME "'"

In production datatype, the QUALIFIED_NAME is used to denote a PROV data type [PROV-DM].

The non terminals STRING_LITERAL, INT_LITERAL, and QUALIFIED_NAME_LITERAL are syntactic sugar for quoted strings with datatype xsd:string, xsd:int, and prov:QUALIFIED_NAME respectively.

In particular, a Literal may be an IRI-typed string (with datatype xsd:anyURI); such IRI has no specific interpretation in the context of PROV.

Note:The productions for prov:QUALIFIED_NAME and INT_LITERAL are conflicting. In the context of a literal, a parser should give precedence to the production for INT_LITERAL.

The following examples respectively are the string "abc", the string (in French) "bonjour", the integer number 1, and the IRI "http://example.org/foo".

  "abc"
  "bonjour"@fr
  "1" %% xsd:integer
  "http://example.org/foo" %% xsd:anyURI

The following example shows a value of type prov:QUALIFIED_NAME (see prov:QUALIFIED_NAME). The prefix ex must be bound to a namespace declared in a namespace declaration.

 
  "ex:value" %% prov:QUALIFIED_NAME
Alternatively, the same value can be expressed using the following convenience notation.
 
  'ex:value'
3.7.3.1 Reserved Type Values

The reserved type values in the PROV namespace are the following.

  1. prov:Bundle
  2. prov:Collection
  3. prov:EmptyCollection
  4. prov:Organization
  5. prov:Person
  6. prov:Plan
  7. prov:PrimarySource
  8. prov:Quotation
  9. prov:Revision
  10. prov:SoftwareAgent

The agent ag is a person (type: prov:Person), whereas the entity pl is a plan (type: prov:Plan).

agent(ag,  [ prov:type='prov:Person' ])
entity(pl, [ prov:type='prov:Plan' ])
3.7.3.2 Time Values

Time instants are defined according to xsd:dateTime [XMLSCHEMA11-2].

[49]    time    ::=    ISODATETIME
[68]    <DIGIT>    ::=    [0-9]
[69]    <ISODATETIME>    ::=    DIGIT DIGIT DIGIT DIGIT "-" DIGIT DIGIT "-" DIGIT DIGIT "T" DIGIT DIGIT ":" DIGIT DIGIT ":" DIGIT DIGIT ( "." DIGIT ( DIGIT (DIGIT)? )? )? ( "Z" | TIMEZONEOFFSET )?
[70]    <TIMEZONEOFFSET>    ::=    ( "+" | "-" ) DIGIT DIGIT ":" DIGIT DIGIT

The third argument in the following usage expression is a time instance, namely 4pm on 2011-11-16.

used(ex:act2, ar3:0111, 2011-11-16T16:00:00)

3.7.4 Namespace Declaration

[50]    namespaceDeclarations    ::=    ( defaultNamespaceDeclaration | namespaceDeclaration ) (namespaceDeclaration)*
[51]    namespaceDeclaration    ::=    "prefix" QUALIFIED_NAME namespace
[53]    namespace    ::=    IRI_REF
[52]    defaultNamespaceDeclaration    ::=    "default" IRI_REF

A namespaceDeclaration consists of a binding between a prefix and a namespace. Every qualified name with this prefix in the scope of this declaration refers to this namespace. The scope of a namespace declaration is the namedBundle or toplevel bundle in which it directly occurs.

In PROV-N, the following prefixes are reserved:

  • prov denotes the PROV namespace with URI http://www.w3.org/ns/prov#
  • xsd denotes the XML Schema namespace with URI http://www.w3.org/2001/XMLSchema#.

A PROV-N document must not redeclare prefixes prov and xsd.

The following example declares three namespaces, one default, and two with explicit prefixes ex1 and ex2.

bundle
  default <http://example.org/0/>
  prefix ex1 <http://example.org/1/>
  prefix ex2 <http://example.org/2/>
...
endBundle

4. Toplevel Bundle

A toplevel bundle is a house-keeping construct of PROV-N capable of packaging up PROV-N expressions and namespace declarations. A toplevel bundle forms a self-contained package of provenance descriptions for the purpose of exchanging them. A toplevel bundle may be used to package up PROV-N expressions in response to a request for the provenance of something ([PROV-AQ]).

Given its status of house keeping construct for the purpose of exchanging provenance expressions, a toplevel bundle is not defined as a PROV-N expression (production expression).

A toplevel bundle, written bundle decls exprs bundles endBundle in PROV-N, contains:

A toplevel bundle's text matches the bundle production.

[1]    bundle    ::=    "bundle" (namespaceDeclarations)? (expression)* (namedBundle)* "endBundle"

The following container contains expressions related to the provenance of entity e2.

bundle
  default <http://anotherexample.org/>
  prefix ex <http://example.org/>

  entity(e2, [ prov:type="File", ex:path="/shared/crime.txt", ex:creator="Alice", 
               ex:content="There was a lot of crime in London last month."])
  activity(a1, 2011-11-16T16:05:00, -,[prov:type="edit"])
  wasGeneratedBy(e2, a1, -, [ex:fct="save"])     
  wasAssociatedWith(a1, ag2, -, [prov:role="author"])
  agent(ag2, [ prov:type='prov:Person' , ex:name="Bob" ])

endBundle

This container could for instance be returned as the result of a query to a provenance store for the provenance of entity e2 [PROV-AQ].

5. Media Type

The media type of PROV-N is text/prov-n. The content encoding of PROV-N content is UTF-8.

See http://www.w3.org/2002/06/registering-mediatype for Register an Internet Media Type for a W3C Spec.

Following text adapted from turtle.
Contact:
Ivan Herman
See also:
How to Register a Media Type for a W3C Specification
Internet Media Type registration, consistency of use
TAG Finding 3 June 2002 (Revised 4 September 2002)

The Internet Media Type / MIME Type for PROV-N is "text/prov-n".

It is recommended that PROV-N files have the extension ".pn" (all lowercase) on all platforms.

It is recommended that PROV-N files stored on Macintosh HFS file systems be given a file type of "TEXT".

This information that follows has been submitted to the IESG for review, approval, and registration with IANA.

Type name:
text
Subtype name:
prov-n
Required parameters:
None
Optional parameters:
charset — this parameter is required when transferring non-ASCII data. If present, the value of charset is always UTF-8.
Encoding considerations:
The syntax of PROV-N is expressed over code points in Unicode [UNICODE5]. The encoding is always UTF-8 [UTF-8].
Unicode code points may also be expressed using an \uXXXX (U+0 to U+FFFF) or \UXXXXXXXX syntax (for U+10000 onwards) where X is a hexadecimal digit [0-9A-F]
Security considerations:
PROV-N is a general-purpose language for describing the provenance of things; applications may evaluate given data to infer more descriptions or to dereference URIs, invoking the security considerations of the scheme for that URI. Note in particular, the privacy issues in [RFC3023] section 10 for HTTP URIs. Data obtained from an inaccurate or malicious data source may lead to inaccurate or misleading conclusions, as well as the dereferencing of unintended URIs. Care must be taken to align the trust in consulted resources with the sensitivity of the intended use of the data; inferences of potential medical treatments would likely require different trust than inferences for trip planning.
PROV-N is used to express arbitrary application data; security considerations will vary by domain of use. Security tools and protocols applicable to text (e.g. PGP encryption, MD5 sum validation, password-protected compression) may also be used on PROV-N documents. Security/privacy protocols must be imposed which reflect the sensitivity of the embedded information.
PROV-N can express data which is presented to the user, for example, label attributes. Application rendering strings retrieved from untrusted PROV-N documents must ensure that malignant strings may not be used to mislead the reader. The security considerations in the media type registration for XML ([RFC3023] section 10) provide additional guidance around the expression of arbitrary data and markup.
PROV-N uses qualified names mappeable to IRIs as term identifiers. Applications interpreting data expressed in PROV-N should address the security issues of Internationalized Resource Identifiers (IRIs) [RFC3987] Section 8, as well as Uniform Resource Identifier (URI): Generic Syntax [RFC3986] Section 7.
Multiple IRIs may have the same appearance. Characters in different scripts may look similar (a Cyrillic "о" may appear similar to a Latin "o"). A character followed by combining characters may have the same visual representation as another character (LATIN SMALL LETTER E followed by COMBINING ACUTE ACCENT has the same visual representation as LATIN SMALL LETTER E WITH ACUTE). Any person or application that is writing or interpreting data in PROV-N must take care to use the IRI that matches the intended semantics, and avoid IRIs that make look similar. Further information about matching of similar characters can be found in Unicode Security Considerations [UNISEC] and Internationalized Resource Identifiers (IRIs) [RFC3987] Section 8.
Interoperability considerations:
There are no known interoperability issues.
Published specification:
This specification.
Applications which use this media type:
No widely deployed applications are known to use this media type. It may be used by some web services and clients consuming their data.
Additional information:
Magic number(s):
PROV-N documents may have the strings 'bundle' near the beginning of the document.
File extension(s):
".pn"
Base URI:
None
Macintosh file type code(s):
"TEXT"
Person & email address to contact for further information:
Ivan Herman, [email protected]
Intended usage:
COMMON
Restrictions on usage:
None
Author/Change controller:
The PROV-N specification is the product of Luc Moreau and Paolo Missier. A W3C Working Group may assume maintenance of this document; W3C reserves change control over this specifications.

A. Acknowledgements

This document has been produced by the PROV Working Group, and its contents reflect extensive discussion within the Working Group as a whole.

Members of the PROV Working Group at the time of publication of this document were: Ilkay Altintas (Invited expert), Reza B'Far (Oracle Corporation), Khalid Belhajjame (University of Manchester), James Cheney (University of Edinburgh, School of Informatics), Sam Coppens (IBBT), David Corsar (University of Aberdeen, Computing Science), Stephen Cresswell (The National Archives), Tom De Nies (IBBT), Helena Deus (DERI Galway at the National University of Ireland, Galway, Ireland), Simon Dobson (Invited expert), Martin Doerr (Foundation for Research and Technology - Hellas(FORTH)), Kai Eckert (Invited expert), Jean-Pierre EVAIN (European Broadcasting Union, EBU-UER), James Frew (Invited expert), Irini Fundulaki (Foundation for Research and Technology - Hellas(FORTH)), Daniel Garijo (Universidad Politécnica de Madrid), Yolanda Gil (Invited expert), Ryan Golden (Oracle Corporation), Paul Groth (Vrije Universiteit), Olaf Hartig (Invited expert), David Hau (National Cancer Institute, NCI), Sandro Hawke (W3C/MIT), Jörn Hees (German Research Center for Artificial Intelligence (DFKI) Gmbh), Ivan Herman, (W3C/ERCIM), Ralph Hodgson (TopQuadrant), Hook Hua (Invited expert), Trung Dong Huynh (University of Southampton), Graham Klyne (University of Oxford), Michael Lang (Revelytix, Inc.), Timothy Lebo (Rensselaer Polytechnic Institute), James McCusker (Rensselaer Polytechnic Institute), Deborah McGuinness (Rensselaer Polytechnic Institute), Simon Miles (Invited expert), Paolo Missier (School of Computing Science, Newcastle university), Luc Moreau (University of Southampton), James Myers (Rensselaer Polytechnic Institute), Vinh Nguyen (Wright State University), Edoardo Pignotti (University of Aberdeen, Computing Science), Paulo da Silva Pinheiro (Rensselaer Polytechnic Institute), Carl Reed (Open Geospatial Consortium), Adam Retter (Invited Expert), Christine Runnegar (Invited expert), Satya Sahoo (Invited expert), David Schaengold (Revelytix, Inc.), Daniel Schutzer (FSTC, Financial Services Technology Consortium), Yogesh Simmhan (Invited expert), Stian Soiland-Reyes (University of Manchester), Eric Stephan (Pacific Northwest National Laboratory), Linda Stewart (The National Archives), Ed Summers (Library of Congress), Maria Theodoridou (Foundation for Research and Technology - Hellas(FORTH)), Ted Thibodeau (OpenLink Software Inc.), Curt Tilmes (National Aeronautics and Space Administration), Craig Trim (IBM Corporation), Stephan Zednik (Rensselaer Polytechnic Institute), Jun Zhao (University of Oxford), Yuting Zhao (University of Aberdeen, Computing Science).

B. References

B.1 Normative references

[IRI]
M. Duerst, M. Suignard. Internationalized Resource Identifiers (IRI). January 2005. Internet RFC 3987. URL: http://www.ietf.org/rfc/rfc3987.txt
[RDF-SPARQL-QUERY]
Andy Seaborne; Eric Prud'hommeaux. SPARQL Query Language for RDF. 15 January 2008. W3C Recommendation. URL: http://www.w3.org/TR/2008/REC-rdf-sparql-query-20080115
[RFC2119]
S. Bradner. Key words for use in RFCs to Indicate Requirement Levels. March 1997. Internet RFC 2119. URL: http://www.ietf.org/rfc/rfc2119.txt
[RFC3023]
M. Murata; S. St.Laurent; D. Kohn. XML Media Types January 2001. Internet RFC 3023. URL: http://www.ietf.org/rfc/rfc3023.txt
[RFC3986]
T. Berners-Lee; R. Fielding; L. Masinter. Uniform Resource Identifier (URI): Generic Syntax. January 2005. Internet RFC 3986. URL: http://www.ietf.org/rfc/rfc3986.txt
[RFC3987]
M. Dürst; M. Suignard. Internationalized Resource Identifiers (IRIs). January 2005. Internet RFC 3987. URL: http://www.ietf.org/rfc/rfc3987.txt
[URI]
T. Berners-Lee; R. Fielding; L. Masinter. Uniform Resource Identifiers (URI): generic syntax. January 2005. Internet RFC 3986. URL: http://www.ietf.org/rfc/rfc3986.txt
[UTF-8]
F. Yergeau. UTF-8, a transformation format of ISO 10646. IETF RFC 3629. November 2003. URL: http://www.ietf.org/rfc/rfc3629.txt
[XML-NAMES]
Richard Tobin; et al. Namespaces in XML 1.0 (Third Edition). 8 December 2009. W3C Recommendation. URL: http://www.w3.org/TR/2009/REC-xml-names-20091208/
[XMLSCHEMA11-2]
Henry S. Thompson; et al. W3C XML Schema Definition Language (XSD) 1.1 Part 2: Datatypes. 5 April 2012. W3C Recommendation URL: http://www.w3.org/TR/2012/REC-xmlschema11-2-20120405/

B.2 Informative references

[PROV-AQ]
Graham Klyne and Paul Groth (eds.) Luc Moreau, Olaf Hartig, Yogesh Simmhan, James Meyers, Timothy Lebo, Khalid Belhajjame, and Simon Miles Provenance Access and Query. 2011, Working Draft. URL: http://www.w3.org/TR/prov-aq/
[PROV-CONSTRAINTS]
James Cheney, Paolo Missier, and Luc Moreau (eds.)Constraints of the Prov Data Model. 2012, Working Draft. URL: http://www.w3.org/TR/prov-constraints/
[PROV-DM]
Luc Moreau and Paolo Missier (eds.) Khalid Belhajjame, Reza B'Far, Stephen Cresswell, Yolanda Gil, Paul Groth, Graham Klyne, Jim McCusker, Simon Miles, James Myers, Satya Sahoo, and Curt TilmesPROV-DM: The PROV Data Model. 2012, Working Draft. URL: http://www.w3.org/TR/prov-dm/
[PROV-RDF]
James CheneyPROV-RDF Mapping 2012, Working in Progress. URL: http://www.w3.org/2011/prov/wiki/ProvRDF
[PROV-SEM]
James Cheney Formal Semantics Strawman. 2011, Work in progress. URL: http://www.w3.org/2011/prov/wiki/FormalSemanticsStrawman
[PROV-XML]
James CheneyPROV-XML Mapping 2012, Working in Progress. URL: http://www.w3.org/2011/prov/wiki/ProvXML
[UNICODE5]
The Unicode Consortium. The Unicode Standard, Version 5.1.0. Addison-Wesley. 2007. ISBN 0-321-48091-0. URL: http://www.unicode.org/versions/Unicode5.1.0/
[UNISEC]
Mark Davis and Michel Suignard. Unicode Security Considerations. 4 August 2010. URL: http://www.unicode.org/reports/tr36/