Iowa Code § 511.13: Disbursements — vouchers — affidavit.

No domestic life insurance company shall make any disbursement of one hundred dollars or more unless the same be evidenced by a voucher signed by or on behalf of the person, firm, or corporation receiving the money and correctly describing the consideration for the payment. If the expenditure be for both services and disbursements the voucher shall set forth the services rendered and an itemized statement of the disbursements made. When such voucher cannot be obtained the expenditure shall be evidenced by an affidavit of some officer or agent of said company describing the character and object of the expenditure and stating the reason for not obtaining such voucher.