Neb. Rev. Stat. §§ 16-115
The corporate name of each city of the first class shall be the City of ......................, and all process whatever affecting any such city shall be served in the manner provided for service of a summons in a civil action. The city shall procure and keep a seal with such emblem and device as it may think proper. Such seal may be either an engraved or ink stamp seal. It shall have included thereon the City of ................, together with date of incorporation, which shall be the seal of the city, and no other seal shall be used by the city. The impression or representation of the seal by stamp shall be sufficient sealing in all cases where sealing is required. An impression or representation of such seal shall be filed in the office of the Secretary of State, together with a resolution of the city council that the same has been duly adopted and is the seal of such city.
Neb. Rev. Stat. §§ 16-115