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<b>let </b><font color="Maroon">G1</font> be   <a href="glib_000.html#NM2">_Graph</a>;<br/><b>let </b><font color="Maroon">G2</font> be   <a href="glib_000.html#NM2">_Graph</a>;<br/>



<a NAME="E1:180"/>
( <font color="Maroon">G1</font> is    <a href="glib_000.html#M2" target="_self">Subgraph</a> of <font color="Maroon">G2</font> &amp; <font color="Maroon">G2</font> is    <a href="glib_000.html#M2" target="_self">Subgraph</a> of <font color="Maroon">G1</font> iff (  <a href="glib_000.html#K6" target="_self">the_Vertices_of</a> <font color="Maroon">G1</font> <a href="hidden.html#R1">=</a>  <a href="glib_000.html#K6" target="_self">the_Vertices_of</a> <font color="Maroon">G2</font> &amp;  <a href="glib_000.html#K7" target="_self">the_Edges_of</a> <font color="Maroon">G1</font> <a href="hidden.html#R1">=</a>  <a href="glib_000.html#K7" target="_self">the_Edges_of</a> <font color="Maroon">G2</font> &amp;  <a href="glib_000.html#K10" target="_self">the_Source_of</a> <font color="Maroon">G1</font> <a href="funct_2.html#R1">=</a>  <a href="glib_000.html#K10" target="_self">the_Source_of</a> <font color="Maroon">G2</font> &amp;  <a href="glib_000.html#K11" target="_self">the_Target_of</a> <font color="Maroon">G1</font> <a href="funct_2.html#R1">=</a>  <a href="glib_000.html#K11" target="_self">the_Target_of</a> <font color="Maroon">G2</font> ) )
 
<b>by </b><i/>;<br/>
<b>hence </b><a NAME="E2:180"/>
( <font color="Maroon">G1</font> <a href="glib_000.html#R5" target="_self">==</a> <font color="Maroon">G2</font> iff ( <font color="Maroon">G1</font> is    <a href="glib_000.html#M2" target="_self">Subgraph</a> of <font color="Maroon">G2</font> &amp; <font color="Maroon">G2</font> is    <a href="glib_000.html#M2" target="_self">Subgraph</a> of <font color="Maroon">G1</font> ) )
 <b>by </b><i/>;<br/>


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