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(*                                                                    *)
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(*                                                                    *)
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(* 02110-1301 USA                                                     *)
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(*          Projet Formel - Calculus of Inductive Constructions V5.10        *)
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(*									     *)
(*	              Pullbacks in SET                  		     *)
(*									     *)
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(*									     *)
(*                     A. SAIBI	  May 95                  		     *)
(*									     *)
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Require Export Pullbacks.
Require Export Setoid_prop.
Require Export SET.
Require Export SetoidPROD.
Set Implicit Arguments.
Unset Strict Implicit.
Section s_pulb_def.
Variables (A B C : Setoid) (f : Map A B) (g : Map C B).
Definition S_pulb_pred (axc : SPROD A C) :=
f (Sprod_l axc) =_S g (Sprod_r axc).

Lemma S_pulb_reg : Reg_law S_pulb_pred.
Canonical Structure S_pulb_constr := Build_Setoid_pred S_pulb_reg.