--- a/model/prov-dm-constraints.html	Mon Apr 02 08:59:46 2012 +0100
+++ b/model/prov-dm-constraints.html	Mon Apr 02 09:09:31 2012 +0100
@@ -219,7 +219,6 @@
 </p>
 
 
-<p>PROV-DM is essentially defined without any constraints  [[PROV-DM]]. This document introduces a further set of concepts underpinning this data model and defines constraints that well-structured provenance descriptions should follow and that provide an interpretation for these descriptions. </p>
 
 
 <p>This specification is one of several specifications, referred to as the PROV family of specifications, defining the various aspects
@@ -239,6 +238,25 @@
 </ul>
 
 
+<p>PROV-DM is essentially defined without any constraints  [[PROV-DM]]. This document introduces a further set of concepts underpinning this data model and defines constraints that well-structured provenance descriptions should follow and that provide an interpretation for these descriptions. </p>
+
+
+<p>In [[PROV-DM]], a data model for provenance has been defined without introducing any constraint that this data model has to satisfy.   First we introduce and refine various concepts such as attributes, event, entity, entity, interval, accounts, which underpin the PROV-DM data model. Using these notions, we explore the constraints
+that the PROV-DM data model has to satisfy. </p> 
+
+<p>Several types of constraints are specified.</p>
+<ul>
+<li>Definitional constraints are constraints directly following the definition of concepts in the PROV data model (<a href="#definitional-constraints">Section 4</a>). </li>
+<li>Account constraints have to be satisfied by provenance descriptions in the context of a given account  (<a href="#account-constraints">Section 5</a>)</li>
+<li>Event ordering constraints provide a "temporal interpretation" for provenance descriptions (<a href="#interpretation">Section 6</a>)</li>
+<li>Structural constraints are further constraints to be satisfied by generation descriptions  (<a href="#structural-constraints">Section 7</a>)</li>
+<li>Collection constraints are the constraints that hold for collections (<a href="#collection-constraints">Section 8</a>)</li>
+</ul>
+</div>
+  
+
+
+<!--
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 <h3>Structure of this Document</h3>
 
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-
+-->
     <section id="conventions"> 
 <h3>Conventions</h3>
 
@@ -523,25 +541,6 @@
 </section>
 
 
- 
-<section id="data-model-constraints">
-<h2>Constraints Applicable to PROV-DM </h2>
-
-<p>In [[PROV-DM]], a data model for provenance has been defined without introducing any constraint that this data model has to satisfy.   In <a href="#prov-dm-refinement">Section 2</a>, various notions have been introduced, attributes, event, entity interval, activity interval, accounts, which underpin the PROV-DM data model. Using these notion, we explore the constraints
-that the PROV-DM data model has to satisfy. </p> 
-
-<div class='note'>
-<p> Overview the kind of constraints</p>
-<ul>
-<li>Definitional constraints (<a href="#definitional-constraints">Section 4</a>)</li>
-<li>Account constraints (<a href="#account-constraints">Section 5</a>)</li>
-<li>Event ordering constraints (<a href="#interpretation">Section 6</a>)</li>
-<li>Structural constraints (<a href="#structural-constraints">Section 7</a>)</li>
-<li>Collection constraints (<a href="#collection-constraints">Section 8</a>)</li>
-</ul>
-</div>
-  
-</section>
 
 <section id="definitional-constraints">