(* IDEM : *)

(* Specifications: *)
Lemma inj_A_1:
forall (m:fmap)(k:dim), inv_hmap m ->
inj_dart (exd m) (A_1 m k).
Lemma expf_A_r_eqc : forall(m:fmap)(k:dim),
inv_qhmap m ->
forall (x y:dart), expf m x (A m k y) -> eqc m x y.