MAYBE Proof: ConCon could not decide if this system is quasi-decreasing. \cite{O02}, p. 214, Proposition 7.2.50 does not apply. System R transformed to U(R). Call external tool: ttt2 - trs 30 Input: ?1(h(y), x) -> y f(x) -> ?1(a, x) ?3(c, x) -> g(f(c), x) ?2(x, x) -> ?3(x, x) g(x, b) -> ?2(f(b), x) a -> h(b) a -> h(c) The external tool could not decide termination.