intros a b aL; elim aL; simpl in |- *; auto.
intros a0 l H' H'0; case H'0; auto.
Qed.

(* Specifications: *)
Lemma addEnd_app :
forall (a : poly A0 eqA ltM) (P : list (poly A0 eqA ltM)),
addEnd a P = P ++ a :: nil.