Okla. Stat. tit. 62, § 34.65
To facilitate the payment of vendor invoices and contract estimates the State Budget Director shall design a uniform jacket to be used by all departments, institutions and agencies of the state, whereon shall be provided summarized information relative to the enclosed invoices or contract estimates, together with a space for the approval of the head of the department, institution or agency approving said vendor invoices or contract estimates for payment. Vendor invoices and contract estimates shall be accepted by the state in lieu of the claim form previously required in the same manner as commercial invoices are paid. Vendor invoices and contract estimates shall be filed with the department, institution or agency receiving the merchandise or services in the same manner as invoices are filed with commercial firms. Upon receipt of invoices or contract estimates the head of the department, institution or agency, or his authorized agent, may approve said documents for payment by executing a certificate of delivery or acceptance of the goods or services. Whereupon, the authorized official of said agency may approve said invoices of contract estimates for payment by enclosing the invoice or contract estimate in a jacket provided for such purpose and affixing his approval in the space provided on the jacket. The provisions of this section shall become effective July 1, 1949, and thereafter commercial invoices shall be accepted in lieu of the standard notarized claim prescribed by the state.
Added by Laws 1949, HB 477, c. 4, § 1, emerg. eff. June 6, 1949.