(CONDITIONTYPE ORIENTED)
(VAR x y)
(RULES
  pin(x) -> pout(g(x))
  pin(x) -> pout(f(y)) | pin(x) == pout(g(y))
)
(COMMENT
  \cite{O01b}, R_P of Example 5.1
  doi: 10.1007/s002000100064
)