--- a/model/prov-constraints.html	Thu Jul 19 16:04:32 2012 +0100
+++ b/model/prov-constraints.html	Thu Jul 19 16:07:29 2012 +0100
@@ -846,7 +846,7 @@
    <div class="definition" id="optional-attributes">
 <ol>
   <li>
-Suppose  <span class="name">r$> is in {<span class="name">entity</span>, <span class="name">activity</span> or <span class="name">agent</span>}.  Then <span class="name">r(a<sub>1</sub>,...,a<sub>n</sub>)</span> holds and does not contain an explicit attribute
+Suppose  <span class="name">r</span> is in {<span class="name">entity</span>, <span class="name">activity</span> or <span class="name">agent</span>}.  Then <span class="name">r(a<sub>1</sub>,...,a<sub>n</sub>)</span> holds and does not contain an explicit attribute
    list <span  class="conditional">IF AND ONLY IF</span>   <span
    class="name">r(a<sub>1</sub>,...,a<sub>n</sub>,[])</span> holds.</li>
      <li>
@@ -940,7 +940,7 @@
     
   <div class="definition" id="optional-placeholders">
     <ol><li>
-Suppose  <span class="name">r$> is in {<span class="name">entity</span>, <span class="name">activity</span> or <span class="name">agent</span>}.  Then   <span class="name">r(a<sub>0</sub>,...,a<sub>i-1</sub>, -, a<sub>i+1</sub>, ...,a<sub>n</sub>) </span> <span class="conditional">IF AND ONLY IF</span> there exists <span class="name">a'</span>
+Suppose  <span class="name">r</span> is in {<span class="name">entity</span>, <span class="name">activity</span> or <span class="name">agent</span>}.  Then   <span class="name">r(a<sub>0</sub>,...,a<sub>i-1</sub>, -, a<sub>i+1</sub>, ...,a<sub>n</sub>) </span> <span class="conditional">IF AND ONLY IF</span> there exists <span class="name">a'</span>
     such that <span class="name">r(a<sub>0</sub>...,a<sub>i-1</sub>,a',a<sub>i+1</sub>,...,a<sub>n</sub>)</span>.
     </li>
     <li>      Similarly, suppose <span class="name">r</span> is in {