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<div><span class="kw">theorem </span><span class="lab"><font color="Green" title="E15">Th15</font></span>: <a NAME="T15"><span class="comment"><font color="firebrick">:: CAT_7:15</font></span><br/></a><div class="add"> for <font color="Olive" title="b1">C</font>, <font color="Olive" title="b2">D</font> being   <a href="cat_6.html#V10" title="CAT_6:attr.10">with_identities</a>   <a href="cat_6.html#L1" title="CAT_6:struct.1">CategoryStr</a>   st <font color="Olive" title="b1">C</font> <a href="cat_6.html#NR4" title="CAT_6:NR.4">~=</a> <font color="Olive" title="b2">D</font> &amp; <font color="Olive" title="b1">C</font> is  <a href="struct_0.html#V2" title="STRUCT_0:attr.2">empty</a>  holds <br/><font color="Olive" title="b2">D</font> is  <a href="struct_0.html#V2" title="STRUCT_0:attr.2">empty</a> </div></div>
