(VAR x) (RULES c(a(x)) -> c(b(x)) b(a(x)) -> c(a(x)) b(c(x)) -> b(a(x)) c(b(x)) -> b(c(x)) b(c(x)) -> b(a(x)) c(b(x)) -> c(a(x)) b(a(x)) -> c(b(x)) b(b(x)) -> c(c(x)) ) (COMMENT submitted by: Johannes Waldmann )