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<div><span class="kw">theorem </span><a NAME="T120"><span class="comment"><font color="firebrick">:: GLIB_001:120</font></span><br/></a><div class="add"> for <font color="Olive" title="b1">G</font> being   <a href="glib_000.html#NM2" title="GLIB_000:NM.2">_Graph</a><br/>  for <font color="Olive" title="b2">W</font> being    <a href="glib_001.html#M3" title="GLIB_001:mode.3">Walk</a> of <font color="Olive" title="b1">G</font> holds <br/> ( <font color="Olive" title="b2">W</font> is  <a href="glib_001.html#V1" title="GLIB_001:attr.1">closed</a>  iff <font color="Olive" title="b2">W</font> <a href="glib_001.html#K6" title="GLIB_001:func.6">.reverse()</a>  is  <a href="glib_001.html#V1" title="GLIB_001:attr.1">closed</a>  )</div></div>
