MAYBE
169.34/55.31	MAYBE
169.34/55.32	
169.34/55.32	Problem:
169.34/55.32	 a(b(b(x1))) -> b(b(a(a(x1))))
169.34/55.32	 a(b(a(x1))) -> b(b(x1))
169.34/55.32	
169.34/55.32	Proof:
169.34/55.32	 Open
169.34/55.32	EOF