MAYBE

Proof:
ConCon could not decide confluence of the system.
\cite{ALS94}, Theorem 4.1 does not apply.
ConCon could not decide whether all critical pairs are joinable or not.
h(g(a)) = p(a) <= b = b, h(f(a)) = k(g(b)):
For all conditions c 'tcap(c.lhs)' is unifiable with c.rhs.
\cite{GNG13}, Theorem 9 does not apply.
\cite{SMI95}, Corollary 4.7 or 5.3 do not apply.