let G1 be _Graph; for G2 being G1 -isomorphic _Graph
for E1, E2 being set
for G3 being reverseEdgeDirections of G1,E1
for G4 being reverseEdgeDirections of G2,E2 holds G4 is G3 -isomorphic
let G2 be G1 -isomorphic _Graph; for E1, E2 being set
for G3 being reverseEdgeDirections of G1,E1
for G4 being reverseEdgeDirections of G2,E2 holds G4 is G3 -isomorphic
let E1, E2 be set ; for G3 being reverseEdgeDirections of G1,E1
for G4 being reverseEdgeDirections of G2,E2 holds G4 is G3 -isomorphic
let G3 be reverseEdgeDirections of G1,E1; for G4 being reverseEdgeDirections of G2,E2 holds G4 is G3 -isomorphic
let G4 be reverseEdgeDirections of G2,E2; G4 is G3 -isomorphic
consider F0 being PGraphMapping of G1,G2 such that
A1:
F0 is isomorphism
by Def23;
consider F being PGraphMapping of G3,G4 such that
F = F0
and
( F0 is weak_SG-embedding implies F is weak_SG-embedding )
and
( F0 is strong_SG-embedding implies F is strong_SG-embedding )
and
A2:
( F0 is isomorphism implies F is isomorphism )
by Th142;
thus
G4 is G3 -isomorphic
by A1, A2; verum