--- a/model/working-copy/prov-dm-constraints.html	Wed Feb 15 11:13:08 2012 +0000
+++ b/model/working-copy/prov-dm-constraints.html	Wed Feb 15 11:18:27 2012 +0000
@@ -485,10 +485,11 @@
 <div class='note'>
 <p> Overview the kind of constraints</p>
 <ul>
-<li>Definitional constraints</li>
-<li>Account constraints</li>
-<li>Event ordering constraints</li>
-<li>Collection constraints</li>
+<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>
   
@@ -501,6 +502,9 @@
 <p>In this section, we revisit elements and relations of PROV-DM, and examine and examine the constraints associated with their definitions.  </p>
 
 
+<div class='note'>
+Proposing to remove the subsections in this section, since some have no constraints.
+</div>
 
 
    <section id="term-element"> 
@@ -1368,7 +1372,7 @@
 
 <p><a href="#definitional-constraints">Section 4</a> provides definitional constraints for data model concepts.
 <a href="#account-constraints">Section 5</a> introduce constraints on descriptions occurring in accounts.
-<a href="#account-constraints">Section 6</a> defines an interpretation of this data model, in terms of event ordering
+<a href="#interpretation">Section 6</a> defines an interpretation of this data model, in terms of event ordering
 constraints.  
 This section introduces further constraints on the structure of PROV-DM descriptions.  Descriptions that satisfy these constraints are said to be <dfn>structurally well-formed</dfn>.  A
 benefit of structurally well-formed provenance descriptions is that further inferences can be made, because descriptions are more precise, and therefore, richer. </p>
@@ -1530,7 +1534,7 @@
 
 
 
-<section>
+<section id="collection-constraints">
 <h3>PROV-DM Collection Constraints</h3>
 
 <div class='note'>