Neb. Rev. Stat. §§ 17-168
The mayor and city council of any city of the second class may adopt by ordinance the proposition to make such purchase, or to erect such facility or facilities, set forth in section 17-164, and before the purchase can be made or facility created, must submit the question to the electors of such city at a general municipal election or at a special election called for that purpose and the question must be approved by a majority of the electors voting on such question. If the question is submitted at a special election, the vote for the purchase or acquisition of such real estate or the purchase or erection of such facility or facilities shall equal at least a majority of the votes cast at the last preceding general election. Notice of the time and place of the election shall be given by publication in a legal newspaper in or of general circulation in such city three successive weeks prior to such election.
Neb. Rev. Stat. §§ 17-168