
theorem Th63:
  for G1 being _Graph, G2 being Subgraph of G1 holds
    G2.supDegree() c= G1.supDegree() &
    G2.supInDegree() c= G1.supInDegree() &
    G2.supOutDegree() c= G1.supOutDegree()
proof
  let G1 be _Graph, G2 be Subgraph of G1;
  set F = (id G1) | G2;
  F is directed weak_SG-embedding by GLIB_010:57;
  hence thesis by Th51, Th56;
end;
