Mich. Comp. Laws § 259.812

Sec. 12. For the purpose of acquiring, purchasing, constructing, improving, enlarging or repairing airports and airport facilities created within or hereafter acquired by the authority, the board may issue self-liquidating bonds of the authority in accordance with the provisions of Act No. 94 of the Public Acts of 1933, as amended, being sections 141.101 to 141.139 of the Compiled Laws of 1948.