YES Proof: This system is quasi-decreasing. By \cite{O02}, p. 214, Proposition 7.2.50. This system is of type 3 or smaller. This system is deterministic. System R transformed to U(R). Call external tool: ttt2 - trs 30 Input: ?1(y, x, y) -> G(x) F(x, y) -> ?1(x, x, y) a -> b DP Processor: DPs: F#(x,y) -> ?1#(x,x,y) TRS: ?1(y,x,y) -> G(x) F(x,y) -> ?1(x,x,y) a() -> b() TDG Processor: DPs: F#(x,y) -> ?1#(x,x,y) TRS: ?1(y,x,y) -> G(x) F(x,y) -> ?1(x,x,y) a() -> b() graph: Qed