Mich. Comp. Laws § 104A.5: Bonds.

Sec. 5.

The city council may borrow money and issue bonds of the city therefor in anticipation of the payment of special assessments in 1 or more special assessment districts, which bonds may be an obligation of the special assessment district or may be both an obligation of the special assessment district and a general obligation of the city. The city council may issue general obligation bonds to defray that portion of the cost and expense of any local public improvement chargeable to the city at large.