Neb. Rev. Stat. §§ 77-1211
When any person brings taxable tangible personal property into this state or into one county thereof from another county after 12:01 a.m. on January 1 and prior to July 1 in any year, it shall be the duty of the owner, within thirty days after July 1, to list and return such property for taxation for the current tax year unless he or she shows to the county assessor under oath and by producing a copy of the listing or assessment duly certified to by the proper officer of the state or county that the property was listed for taxation for the current tax year in some other county in this state or in some other state or territory of the United States or that such property has been received by him or her in exchange for money or property already listed for taxation for the current tax year. The county assessor shall at once assess such property and shall enter the same on the tax roll.
Neb. Rev. Stat. §§ 77-1211