NO Problem: c() -> c() b() -> f(c()) h(b(),h(a(),f(h(a(),f(f(f(b()))))))) -> h(a(),f(a())) b() -> h(b(),a()) h(f(b()),c()) -> f(c()) Proof: Nonconfluence Processor: terms: h(f(c()),h(a(),f(h(a(),f(f(f(b()))))))) *<- h(b(),h(a(),f(h(a(),f(f(f(b()))))))) ->* h(a(),f(a())) Qed