Lemma hzmultgeh0gth0 { m n : hz } ( ism : hzgeh m 0 ) ( isn : hzgth n 0 ) : hzgeh ( m * n ) 0 .
Require Import UniMath.MoreFoundations.PartA. Require Import UniMath.Algebra.Monoids. Require Import UniMath.Algebra.Groups.