\forall mult: A \to A \to A.
\forall H: (\forall x,y,z:A.mult z (inv (mult (inv (mult (inv (mult z y)) x)) (inv (mult y (mult (inv y) y))))) = x).
\forall a,b:A. mult a (inv a)= mult b (inv b).
-intros.auto paramodulation.
+intros.auto paramodulation;exact a.
qed.