---- CR(R cup S)
---- [Klein and Hirokawa, 2012]
R:
f(i(x),g(a())) -> f(j(x,x),g(b()))
b() -> a()
i(x) -> j(x,x)
S:

CP_S(R):
f(j(___y70,___y70),g(a())) -> f(j(___y70,___y70),g(b()))
CR(S):
see below.

---- CR(R)
---- [Hirokawa and Middeldorp, 2011]
R:

CPS'(R):

CP(R):