Sections 14-1731 to 14-1740 and of any ordinance authorizing the issuance of bonds under such sections shall constitute a contract with the holders of such bonds, and any holder of a bond or bonds or any of the coupons of any bond or bonds of a city of the metropolitan class, issued under such sections may either in law or in equity, by suit, action, mandamus, or other proceedings, enforce and compel the performance of all duties required by such sections or by the ordinance authorizing the bonds, including the making and collection of sufficient charges and fees for service and the use of such charges and fees, and the application of income and revenue from such charges and fees.
Neb. Rev. Stat. §§ 14-1739