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

CR(S):
see below.

---- CR(R)
---- [Hirokawa and Middeldorp, 2011]
R:
f(x) -> g(x,h(x))
b() -> h(b())
CPS'(R):

CP(R):