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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">:: ROBBINS3:28</font></span><br/></a><div class="add"> for <font color="Olive" title="b1">L</font> being   non  <a href="struct_0.html#V2" title="STRUCT_0:attr.2">empty</a>   <a href="robbins3.html#L4" title="ROBBINS3:struct.4">OrthoLattRelStr</a>   st <font color="Olive" title="b1">L</font> is  <a href="robbins3.html#V8" title="ROBBINS3:attr.8">involutive</a>  &amp; <font color="Olive" title="b1">L</font> is  <a href="robbins3.html#V9" title="ROBBINS3:attr.9">with_Top</a>  &amp; <font color="Olive" title="b1">L</font> is  <a href="robbins1.html#V10" title="ROBBINS1:attr.10">de_Morgan</a>  &amp; <font color="Olive" title="b1">L</font> is  <a href="lattices.html#V10" title="LATTICES:attr.10">Lattice-like</a>  &amp; <font color="Olive" title="b1">L</font> is  <a href="robbins3.html#V10" title="ROBBINS3:attr.10">naturally_sup-generated</a>  holds <br/>( <font color="Olive" title="b1">L</font> is  <a href="oposet_1.html#V12" title="OPOSET_1:attr.12">Orthocomplemented</a>  &amp; <font color="Olive" title="b1">L</font> is  <a href="oposet_1.html#V6" title="OPOSET_1:attr.6">PartialOrdered</a>  )</div></div>
