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<div><span class="kw">theorem </span><span class="lab"><font color="Green" title="E29">Th28</font></span>: <a NAME="T28"><span class="comment"><font color="firebrick">:: AOFA_000:28</font></span><br/></a><div class="add"> for <font color="Olive" title="b1">A</font> being   <a href="unialg_1.html#NM1" title="UNIALG_1:NM.1">Universal_Algebra</a>  st  <a href="unialg_2.html#K6" title="UNIALG_2:func.6">Constants</a> <font color="Olive" title="b1">A</font> <a href="hidden.html#R1" title="HIDDEN:pred.1">=</a>  <a href="xboole_0.html#K1" title="XBOOLE_0:func.1">{}</a>  holds <br/> <a href="struct_0.html#K1" title="STRUCT_0:func.1">{}</a> <font color="Olive" title="b1">A</font> is  <a href="unialg_2.html#V1" title="UNIALG_2:attr.1">opers_closed</a> </div></div>
