N.D. Cent. Code § 21-03-19
Bonds issued under this chapter must be authorized by resolution, bear such date or dates, be in such denomination or denominations, be in such form, be subject to redemption with or without premium, and be subject to such other terms or conditions as in the judgment of the municipality are in the public interest of the municipality, and must provide that the last installment of principal falls due not more than twenty years from the date of the bonds. The requirements of this section apply to each new issue of bonds, or if so determined by the governing body, to the bonds of a new issue combined with all of the outstanding bonds of one or more designated issues of bonds previously issued and similarly payable from taxes or other sources of revenues, or both, as the case may be.
N.D.C.C. § 21-03-19