Definition eqbST (cp1 cp2 : tST) :=
    eqbList (PosSort.sort (CPToList cp1)) (PosSort.sort (CPToList cp2)).

(* Specifications: *)
Lemma eqbST_eqST : forall cp1 cp2, eqbST cp1 cp2 = true <-> eqST cp1 cp2.