theorem Th49: :: GLIB_000:49

for G1 being _Graph
for V being set
for G2 being removeVertices of G1,V st V c< the_Vertices_of G1 holds
( the_Vertices_of G2 = (the_Vertices_of G1) \ V & the_Edges_of G2 = G1 .edgesBetween ((the_Vertices_of G1) \ V) )