YES 1: f(a()) -> f(g(b(),b())) 2: a() -> g(c(),c()) 3: c() -> d() 4: d() -> b() 5: b() -> d() @Rule Labeling --- R 1: f(a()) -> f(g(b(),b())) 2: a() -> g(c(),c()) 3: c() -> d() 4: d() -> b() 5: b() -> d() --- S 1: f(a()) -> f(g(b(),b())) 2: a() -> g(c(),c()) 3: c() -> d() 4: d() -> b() 5: b() -> d()