Okla. Stat. tit. 58, § 338

Every claim allowed by the personal representative, and approved by the judge, must, within thirty (30) days after approval by the judge, be filed in the district court and ranked among the acknowledged debts of the estate, to be paid in due course of administration. If the claimant has left any original voucher in the hands of the personal representative, or suffered the same to be filed in court, he may withdraw the same when a copy of the same has been already, or is then, attached to his claim.