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(*         *      The Rocq Prover / The Rocq Development Team           *)
(*  v      *         Copyright INRIA, CNRS and contributors             *)
(* <O___,, * (see version control and CREDITS file for authors & dates) *)
(*   \VV/  **************************************************************)
(*    //   *    This file is distributed under the terms of the         *)
(*         *     GNU Lesser General Public License Version 2.1          *)
(*         *     (see LICENSE file for the text of the license)         *)
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(*                      Evgeny Makarov, INRIA, 2007                     *)
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Require Export ZLt.
Module ZAddOrderProp (Import Z : ZAxiomsMiniSig').
Include ZOrderProp Z.
(** Theorems that are either not valid on N or have different proofs on N and Z *)

Theorem add_neg_neg : forall n m, n < 0 -> m < 0 -> n + m < 0.