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<div><span class="kw">theorem </span><span class="lab"><font color="Green" title="E20">Th23</font></span>: <a NAME="T23"><span class="comment"><font color="firebrick">:: WAYBEL25:23</font></span><br/></a><div class="add"> for <font color="Olive" title="b1">X</font> being   <a href="pre_topc.html#NM1" title="PRE_TOPC:NM.1">TopSpace</a><br/>  for <font color="Olive" title="b2">A</font> being   <a href="pre_topc.html#V3" title="PRE_TOPC:attr.3">open</a>  <a href="struct_0.html#NM2" title="STRUCT_0:NM.2">Subset</a> of <span class="p1">(<span class="default"><a href="waybel25.html#K1" title="WAYBEL25:func.1">Omega</a> <font color="Olive" title="b1">X</font></span>)</span> holds  <font color="Olive" title="b2">A</font> is  <a href="waybel_0.html#V13" title="WAYBEL_0:attr.13">upper</a> </div></div>
