
theorem Th84:
  for G1 being _Graph, G2 being G1-Disomorphic _Graph
  for G3 being DGraphComplement of G1, G4 being DGraphComplement of G2
  holds G4 is G3-Disomorphic
proof
  let G1 be _Graph, G2 be G1-Disomorphic _Graph;
  let G3 be DGraphComplement of G1, G4 be DGraphComplement of G2;
  set G5 = the DSimpleGraph of G1;
  set G6 = the DSimpleGraph of G2;
  G6 is G5-Disomorphic by GLIB_010:174;
  hence thesis by Th83;
end;
