remove dead link

Author: davidhassell

docs/aggregation_rules.html

@@ -123,8 +123,8 @@ <h3>Related Topics</h3>
 <span id="id1"></span><h1><strong>Aggregation rules</strong><a class="headerlink" href="#aggregation-rules" title="Link to this heading">¶</a></h1>
 <hr class="docutils" />
 <p>Version 3.20.0 for version 1.13 of the CF conventions.</p>
-<p><em>David Hassell and Jonathan Gregory (2012)</em></p>
-<p><a class="reference external" href="https://cf-trac.llnl.gov/trac/ticket/78">https://cf-trac.llnl.gov/trac/ticket/78</a></p>
+<p><em>David Hassell and Jonathan Gregory (2012, with many updates since)</em></p>
+
 <p>Aggregation is the combination of two field constructs <a class="reference internal" href="introduction.html#term-field-construct"><span class="xref std std-term">field
 constructs</span></a> to create a new field construct that
 occupies a “larger” domain. In practice, this means combining the two
@@ -352,4 +352,4 @@ <h3>Related Topics</h3>
 
 
   </body>
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+</html>