Fact Cint_span_key s : pred_key (Cint_span s).Canonical Cint_span_keyed s := KeyedPred (Cint_span_key s).

(* Specifications: *)
Lemma mem_Cint_span s : {subset s <= Cint_span s}.
Lemma Cint_span_zmod_closed s : zmod_closed (Cint_span s).