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(* 02110-1301 USA                                                     *)
(* Contribution to the Coq Library   V6.3 (July 1999)                    *)
(****************************************************************************)
(*                 The Calculus of Inductive Constructions                  *)
(*                                                                          *)
(*                                Projet Coq                                *)
(*                                                                          *)
(*                     INRIA                        ENS-CNRS                *)
(*              Rocquencourt                        Lyon                    *)
(*                                                                          *)
(*                                 Coq V6.1                                 *)
(*                               Oct 1st 1996                               *)
(*                                                                          *)
(****************************************************************************)
(*                                  Tait.v                                  *)
(****************************************************************************)
Set Implicit Arguments.
Unset Strict Implicit.

Theorem Strip :
forall (U : Type) (R : Relation U),
Strongly_confluent R ->
forall x b : U,
Rstar R x b -> forall a : U, R x a -> exists z : U, Rstar R a z /\ R b z.