Section Fpullback_limit_def.
Variables (C : Category) (G : Functor PULB C).
SubClass Fpullback1 := Limit G.
Variable l : Fpullback1.
Definition Fibred1_prod := Lim l.
Definition Fibred1_p : Fibred1_prod --> G P1 := Limiting_cone l P1.
Definition Fibred1_q : Fibred1_prod --> G P3 := Limiting_cone l P3.

Lemma Prf_pb1_law1 :
Pullback_law1 (FMor G F12) (FMor G F32) Fibred1_p Fibred1_q.