
theorem
  for G1, G2 being _Graph, F be one-to-one PGraphMapping of G1, G2
  st F is total continuous holds F" is continuous
proof
  let G1, G2 be _Graph, F be one-to-one PGraphMapping of G1, G2;
  assume F is total continuous;
  then F" is onto by FUNCT_1:33;
  hence F" is continuous;
end;
