Lemma hzmultlth0geh0 { m n : hz } ( ism : hzlth m 0 ) ( isn : hzgeh n 0 ) : hzleh ( m * n ) 0 .
Require Import UniMath.MoreFoundations.PartA. Require Import UniMath.Algebra.Monoids. Require Import UniMath.Algebra.Groups.