proposition: Lemma afixMin G H : G \subset D -> H \subset D -> 'Fix_to(G * H) = 'Fix_to(G) :&: 'Fix_to(H).
proof: Proof. by move=> sGD sHD; rewrite -afix_gen_in ?mul_subG // genM_join afixYin. Qed.
imports: mathcomp(ssreflect ssrbool ssrfun eqtype ssrnat div seq) mathcomp(fintype bigop finset fingroup morphism perm) mathcomp(automorphism quotient)