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

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

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

CPS'(R):

CP(R):