--- a/model/ProvenanceModel.html	Wed Jul 20 17:33:42 2011 +0100
+++ b/model/ProvenanceModel.html	Wed Jul 20 17:54:05 2011 +0100
@@ -556,7 +556,7 @@
 
 <h3>IVP of</h3>
 
-<p><dfn id="dfn-IVPof">IVP of</dfn> represents a relationship between two characterized entities that are the same entity over some continuous time interval.</p>
+<p><dfn id="dfn-IVPof">IVP of</dfn> is a relationship between two characterized entities that are asserted to be the same over some continuous time interval.</p>
 
 <p>An IVP assertion is denoted <b>IVPof(B,A)</b>, where A and B are two BOBs.
 
@@ -582,22 +582,17 @@
 </p>
 
 
-<div class="note"> What follows below definitely needs revision</div>
-
-<div class="note"> I didn't reall attempt any serious rewriting here</div>
-
-<p>Let A and B be two entity states. An assertion "B is an IVP of A" 
+<p>Let A and B be two BOBs. An assertion "B is an IVP of A" 
 indicates that, for its asserter, A and B represent the same entity in 
-the world, and the entity states modelled by A and B are consistent.</p>
+the world.</p>
 
 
 <p>
-An assertion "B is an IVP of A" holds, <em>only if</em>: 
+An assertion "B is an IVP of A" holds over the temporal intersection of A and B, <em>only if</em>: 
 <ol>
-  <li>the characteristics A and B share must have equal values
-  </li><li>something that changed in A has become a characteristics of B
+  <li>the attributes that A and B share must have equal values</li>
+  <li>B has some attribute that A does not have
 </li></ol>
-Furthermore, B has invariant properties that have no correspondent for A
 </p>
 </section>