MAYBE
(ignored inputs)COMMENT doi:10.1016/0890-5401 ( 90 ) 90015-A [24] Example 1 submitted by: Takahito Aoto , Junichi Yoshida , and Yoshihito Toyama
Rewrite Rules:
   [ a -> f(a,b),
     f(a,b) -> f(b,a) ]
Apply Direct Methods...
Inner CPs:
   [ f(f(a,b),b) = f(b,a) ]
Outer CPs:
   [  ]
Linear
(inner) Parallel CPs: (not computed)
unknown Toyama (Parallel CPs)
Direct Methods: Can't judge

Combined result: Can't judge
80.trs: Failure(unknown CR)
(0 msec.)