--- a/model/prov-constraints.html	Thu Jul 19 10:53:54 2012 +0100
+++ b/model/prov-constraints.html	Thu Jul 19 10:55:31 2012 +0100
@@ -1642,7 +1642,7 @@
   <hr />
    <p id='key_relation2_text'> Furthermore,  identifiers
    of relationships in PROV uniquely identify a relation (except for wasInfluencedBy), through
-  the following key constraints:
+  the following key constraint:
   </p>
   <div class='constraint' id='key-relation2'>
     <p>The <span
@@ -1661,9 +1661,8 @@
 </p>   </div>
 
    <hr />
-   <p id='entity-activity-disjoint_text'> Furthermore,  identifiers
-   of relationships in PROV uniquely identify a relation (except for wasInfluencedBy), through
-  the following key constraints:
+   <p id='entity-activity-disjoint_text'> Furthermore,  the set of entities and activities are disjoint, expressed by 
+  the following constraint:
   </p>
   <div class='constraint' id='entity-activity-disjoint'>
     <p>It is not the case that <span  class="name">entity(id,attrs1)</span> and