(VAR x y z)
(RULES
   *(e,x) -> x
   *(-(x),x) -> e
   *(*(x,y),z) -> *(x,*(y,z))
   *(-(x),*(x,y)) -> y
   *(x,e) -> x
   -(e) -> e
   -(-(x)) -> x
   *(x,-(x)) -> e
   *(x,*(-(x),y)) -> y
   -(*(x,y)) -> *(-(y),-(x))
)
(COMMENT A Complete Set of Axioms for Group Theory, Example 1 of \cite{KB70})