Mich. Comp. Laws § 247.668f: Approval of construction; sale price of bonds.

Sec. 18f.

If the aggregate maturities of the bonds exceed 15 years, the bonds shall not be issued until the state transportation department has approved the construction to be financed by the proceeds of the bonds. The sale price of the bonds shall not be less than the minimum price specified in the proceedings authorizing their issuance.