“…A related result is that of ACZ~L, BELOUSOV, and Hosszu [3,Theorem 3] Noting the abundance of surjectivity, the commutativity of o follows by setting x = e2 in the above and then the associativity is immediate. A function f:G-+G' between two topological groupoids is a homomorphism if f(xy) =f(x) f(y) for all x, yeG and is an iseomorphism if, in addition, it is a homeomorphism.…”