(from
Fissore, Olivier and Gnaedig, Isabelle and Kirchner, Hélène. 
Outermost ground termination - Extended version. Technical Report A02-R-493
2002, LORIA, Nancy, France
)

(VAR x)

(RULES
	f(x)	-> g(f(x))
	g(f(x))	-> x
	g(x) -> a
)