let G2 be _Graph; :: thesis: for G1 being Supergraph of G2 holds
( the_Source_of G2 = (the_Source_of G1) | (the_Edges_of G2) & the_Target_of G2 = (the_Target_of G1) | (the_Edges_of G2) )
let G1 be Supergraph of G2; :: thesis: ( the_Source_of G2 = (the_Source_of G1) | (the_Edges_of G2) & the_Target_of G2 = (the_Target_of G1) | (the_Edges_of G2) )
G2 is Subgraph of G1 by Th61;
hence ( the_Source_of G2 = (the_Source_of G1) | (the_Edges_of G2) & the_Target_of G2 = (the_Target_of G1) | (the_Edges_of G2) ) by GLIB_000:45; :: thesis: verum