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<div><span class="kw">theorem </span><span class="lab"><font color="Green" title="E38">Th56</font></span>: <a NAME="T56"><span class="comment"><font color="firebrick">:: CLASSES2:56</font></span><br/></a><div class="add"> for <font color="Olive" title="b1">U</font> being   <a href="classes2.html#NM1" title="CLASSES2:NM.1">Universe</a> holds   <a href="xboole_0.html#K1" title="XBOOLE_0:func.1">{}</a>  <a href="tarski.html#R2" title="TARSKI:pred.2">in</a> <font color="Olive" title="b1">U</font></div></div>
