End NonZero.
Section Irreducible.
Hypothesis irr_p : irreducible_poly p.
Let nz_p : p != 0. Proof. exact: irredp_neq0. Qed.

(* The Vector axiom requires irreducibility. *)
Lemma min_subfx_vectAxiom : Vector.axiom (size p).-1 subfx_lmodType.
Definition SubfxVectMixin := VectMixin min_subfx_vectAxiom.