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<div><span class="kw">theorem </span><a NAME="T19"><span class="comment"><font color="firebrick">:: ISOCAT_1:19</font></span><br/></a><div class="add"> for <font color="Olive" title="b1">A</font>, <font color="Olive" title="b2">B</font>, <font color="Olive" title="b3">C</font>, <font color="Olive" title="b4">D</font> being   <a href="cat_1.html#NM4" title="CAT_1:NM.4">Category</a>  st <font color="Olive" title="b1">A</font> <a href="isocat_1.html#NR2" title="ISOCAT_1:NR.2">~=</a> <font color="Olive" title="b2">B</font> &amp; <font color="Olive" title="b3">C</font> <a href="isocat_1.html#NR2" title="ISOCAT_1:NR.2">~=</a> <font color="Olive" title="b4">D</font> holds <br/><span class="p1"><a href="cat_2.html#K6" title="CAT_2:func.6">[:</a><span class="default"><font color="Olive" title="b1">A</font>,<font color="Olive" title="b3">C</font></span><a href="cat_2.html#K6" title="CAT_2:func.6">:]</a></span> <a href="isocat_1.html#NR2" title="ISOCAT_1:NR.2">~=</a> <span class="p1"><a href="cat_2.html#K6" title="CAT_2:func.6">[:</a><span class="default"><font color="Olive" title="b2">B</font>,<font color="Olive" title="b4">D</font></span><a href="cat_2.html#K6" title="CAT_2:func.6">:]</a></span></div></div>
