Neb. Rev. Stat. §§ 19-411
The city council members in a city under the commission plan of government shall qualify and give bond in the manner and amount provided by the existing laws governing the city in which they are elected. If any vacancy occurs in the office of city council member, the vacancy shall be filled as provided in section 32-568. The terms of office of all other elective or appointive officers in force within or for any such city shall cease as soon as the city council selects or appoints their successors and such successors qualify and give bond as by law provided or as soon as such city council by resolution declares the terms of any such elective or appointive officers at an end or abolishes or discontinues any of such offices.
Neb. Rev. Stat. §§ 19-411