reserve G, G1, G2 for _Graph, H for Subgraph of G;

theorem Th8:
  for V being non empty Subset of the_Vertices_of G1
  st V c= the_Vertices_of G2 holds createGraph(V) is Subgraph of G2
proof
  let V be non empty Subset of the_Vertices_of G1;
  assume A1: V c= the_Vertices_of G2;
  for e being set st e in the_Edges_of createGraph(V) holds
    (the_Source_of createGraph(V)).e = (the_Source_of G2).e &
    (the_Target_of createGraph(V)).e = (the_Target_of G2).e;
  hence thesis by A1, XBOOLE_1:2, GLIB_000:def 32;
end;
