theorem Th11: :: FUNCTOR1:11

for C1 being non empty AltGraph
for C2, C3 being non empty reflexive AltGraph
for F being feasible FunctorStr over C1,C2
for G being FunctorStr over C2,C3 st F is surjective & G is surjective holds
G * F is surjective by Th8, Th9;