Definition dta_ref_ok_check (d : DTA) : bool :=
match d with
| dta p a => predta_ref_ok_check p
end.

(* Specifications: *)
Lemma dta_ref_ok_check_correct :
forall d : DTA, DTA_ref_ok d -> dta_ref_ok_check d = true.
Lemma dta_ref_ok_check_complete :
forall d : DTA, dta_ref_ok_check d = true -> DTA_ref_ok d.