Section s_pulb_diese_def.
Variables (D : Setoid) (t1 : Map D A) (t2 : Map D C).
Hypothesis H : Pullback_eq1 f g t1 t2.
Canonical Structure S_pulb_fun (d : D) :=
Build_SubType (Check_S_pulb_constr d).

Lemma S_pulb_map_law : Map_law S_pulb_fun.