Neb. Rev. Stat. §§ 46-197
The bonds shall be each of the denomination of not less than one hundred dollars or more than five hundred dollars, negotiable in form, executed in the name of the district, and signed by the president and secretary, and the seal of the district shall be affixed thereto. They shall be numbered consecutively as issued and bear date at the time of their issue. Coupons for the interest shall be attached to each bond, signed by the president and secretary. The bonds shall express on their face that they were issued by the authority of Chapter 46, article 1. Each bond shall be made payable at the given time for its entire amount, and the bonds shall be issued in series only, each series being payable at the expiration of a certain number of years.
Neb. Rev. Stat. §§ 46-197