(VAR x y)
(RULES
  F(x,y) -> c(y)
  G(x) -> x
  f(x) -> g(x)
  g(x) -> c(x)
)
(COMMENT
[20] Example 4.2.2
submitted by: Takahito Aoto, Junichi Yoshida, and Yoshihito Toyama
)