Iowa Code § 353.7: Contents of warrants.

All such anticipatory warrants shall be signed by the chairperson of the board of supervisors and attested by the county auditor with the auditor’s official seal attached thereto, and dated as of the date of sale, and shall not be sold for less than par value. Said bonds may be drawn and sold from time to time as the need for funds to carry out the purpose of this chapter arises.