(CONDITIONTYPE ORIENTED)
(VAR x x' x'' y)
(RULES
  f(x, x') -> g(y, y) | x == y, x' == y
  h(x, x', x'') -> c | x == y, x' == y, x'' == y
)
(COMMENT
  \cite{TO94}, Example 1
  doi: 10.1007/3-540-60381-6_19
)