(VAR x)
(RULES
  a(s(x)) -> s(a(x))
  b(a(b(s(x)))) -> a(b(s(a(x))))
  b(a(b(b(x)))) -> a(b(a(b(x))))
  a(b(a(a(x)))) -> b(a(b(a(x))))
)
(COMMENT
TPDB SRS_Standard/Zantema_04/z008
)