Section InjmFrobenius.
Variables (gT rT : finGroupType) (D G : {group gT}) (f : {morphism D >-> rT}).
Implicit Types (H K : {group gT}) (sGD : G \subset D) (injf : 'injm f).

Lemma injm_Frobenius_ker K sGD injf :
[Frobenius G with kernel K] -> [Frobenius f @* G with kernel f @* K].