0.80/1.38	MAYBE
0.80/1.38	
0.80/1.38	Problem:
0.80/1.38	plus(0(), y) -> y
0.80/1.38	plus(s(x), y) -> plus(x, s(y))
0.80/1.38	f(x, y) -> z <= plus(x, y) = plus(z, z')
0.80/1.38	
0.80/1.39	Proof:
0.80/1.39	ConCon could not decide confluence of the system.
0.80/1.39	\cite{GNG13}, Theorem 9 does not apply.
0.80/1.39	
0.80/1.39	EOF