---- CR(R) ---- [van Oostrom, RTA 2008]. R: W(W(x)) -> W(x) B(I(x)) -> W(x) W(B(x)) -> B(x) F(H(x),y) -> F(H(x),G(y)) F(x,I(y)) -> F(G(x),I(y)) G(x) -> x Label: [W(W(x)) -> W(x)] = 0 [B(I(x)) -> W(x)] = 1 [W(B(x)) -> B(x)] = 0 [F(H(x),y) -> F(H(x),G(y))] = 5 [F(x,I(y)) -> F(G(x),I(y))] = 0 [G(x) -> x] = 0