The commissioner who is the head of each department shall audit all accounts against it, but before payment the accounts shall be acted upon and approved by at least three members of the board of city commissioners. Approval by at least three members of the board of city commissioners shall be recorded in the record of the board and this shall be sufficient to indicate approval without requiring the approving members to sign or initial the voucher or order for payment of the account.
N.D.C.C. § 40-09-13