proposition: Lemma solvable_ext_refl E : solvable_ext E E.
proof: Proof. by apply/solvable_extP; exists E; rewrite subvv galois_refl/= galvv solvable1. Qed.
imports: HB(structures) mathcomp(all_ssreflect all_fingroup all_algebra) mathcomp(all_solvable all_field) Abel(various char0)