--- a/org/index.html	Sat Feb 16 13:16:17 2013 +0000
+++ b/org/index.html	Sat Feb 16 15:17:35 2013 +0000
@@ -478,9 +478,10 @@
 	org:resultingOrganization <http://example.com/DCSF> .
 </pre>
 
-<p>We can use terms from the PROV-O vocabulary to further describe the
-  change event (for example the period of time over which it
-  occurred).<p>
+<p>An application can use terms from the PROV-O vocabulary to further describe the
+  change event, for example the period of time over which it
+  occurred. Such usage of PROV-O terms should take into account the
+  semantic constraints [[PROV-CONSTRAINTS]] of the PROV model. <p>
 
 <p>It is sometimes convenient to be able to directly link from an
   organization to a previous organization from which it descended. This

--- a/org/respec-ref.js	Sat Feb 16 13:16:17 2013 +0000
+++ b/org/respec-ref.js	Sat Feb 16 15:17:35 2013 +0000
@@ -12,6 +12,11 @@
           berjon.biblio["RFC2616"] = "<cite><a href=\"http://www.w3.org/Protocols/rfc2616/rfc2616.html\">Hypertext Transfer Protocol -- HTTP/1.1</a></cite>, R. Fielding; et al. June 1999. Internet RFC 2616. URL: http://www.w3.org/Protocols/rfc2616/rfc2616.html.";
 	  berjon.biblio["VCARD"] =  "R. Iannella; et al. <cite><a href=\"http://www.w3.org/TR/vcard-rdf/\">Representing vCard Objects in RDF</a></cite>, January 2010. W3C Member Sumission 20 January 2010. URL: <a href=\"http://www.w3.org/Submission/2010/SUBM-vcard-rdf-20100120\">http://www.w3.org/Submission/2010/SUBM-vcard-rdf-20100120</a>";
 	  berjon.biblio["PROV-O"] =  "Timothy Lebo, Satya Sahoo, Deborah McGuinness, <cite><a href=\"http://www.w3.org/TR/2012/WD-prov-o-20120724/\">PROV-O: The PROV Ontology</a></cite>, W3C Working Draft 24 July 2012. URL: <a href=\"http://www.w3.org/TR/prov-o/\">http://www.w3.org/TR/prov-o/</a>";
+	  berjon.biblio["PROV-CONSTRAINTS"] = 
+          "James Cheney; Paolo Missier; Luc Moreau; eds. "+
+          "<a href=\"http://www.w3.org/TR/2013/PR-prov-constraints-20130312/\"><cite>Constraints of the PROV Data Model</cite></a>. "+
+          "12 March 2013, W3C Proposed Recommendation. "+
+          "URL: <a href=\"http://www.w3.org/TR/2013/PR-prov-constraints-20130312/\">http://www.w3.org/TR/2013/PR-prov-constraints-20130312/</a>",
 	  berjon.biblio["GOOD-RELATIONS"] =  "Martin Hepp, <cite><a href=\"http://www.heppnetz.de/ontologies/goodrelations/v1.html\">GoodRelations Language Reference</a></cite>, Version 1.0, 1 October 2011,  URL: <a href=\"http://www.heppnetz.de/ontologies/goodrelations/v1.html\">http://www.heppnetz.de/ontologies/goodrelations/v1.html</a>";
 
                 // process the document before anything else is done
@@ -127,4 +132,4 @@
                     p.replaceChild(sp, item) ;
                 }
             }
-    } ;
\ No newline at end of file
+    } ;