proposition: Lemma set_subset_wmax_elt (S: r' ⊆ r) : wmax_elt r ⊆₁ wmax_elt r'.
proof: Proof. unfold wmax_elt, inclusion, set_subset in *; intuition; eauto. Qed.
imports: HahnBase HahnList HahnSets HahnRelationsBasic HahnEquational HahnRewrite Arith Setoid