Module Type NSubProp (Import N : NAxiomsMiniSig').
Include NMulOrderProp N.
(* This could be proved by adding m to both sides. Then the proof would use add_sub_assoc and sub_0_le, which is proven below. *)
(** Sub and order *)

Theorem le_sub_le_add_l : forall n m p, n - m <= p <-> n <= m + p.