Neb. Rev. Stat. § 17-969: Neb. Rev. Stat. § 17-969

The city council or village board of trustees shall each year until the bonds issued under the authority of section 17-967 be paid, levy upon the taxable property in the city of the second class or village, a tax sufficient to pay the interest and five percent of the principal as a sinking fund; and at the tax levy preceding the maturity of any such bonds, levy an amount sufficient to pay the principal and interest due on such bonds.