Canonical Structure Fpulb_map (x y : PULB) :=
  Build_Map (Fpulb_map_law (x:=x) (y:=y)).

(* Specifications: *)
Lemma Fpulb_comp_law : Fcomp_law Fpulb_map.
Lemma Fpulb_id_law : Fid_law Fpulb_map.