County treasurers shall have and keep an official seal, which may be either an engraved or an ink stamp seal, and which shall have included thereon the name of the county followed by the word County, the name of the state, and the words County Treasurer. Each county treasurer shall affix an impression or representation of such seal to every certificate of tax sale and tax deed made by him.
Neb. Rev. Stat. §§ 77-1857