Neb. Rev. Stat. §§ 52-118.01
Every person who has furnished labor or material in the prosecution of the work provided for in the contract set out in subsection (1) of section 52-118, in respect of which a bond is or bonds are furnished under such section, and who has not been paid in full therefor before the expiration of a period of ninety days after the day on which the last of the labor was done or performed by him or her or material was furnished or supplied by him or her for which such claim is made shall have the right to sue on such bond or bonds for the amount or the balance thereof unpaid at the time of the institution of such suit and to prosecute the action to final execution and judgment for the sum or sums justly due him or her. Any person having a direct contractual relationship with a subcontractor but no contractual relationship, express or implied, with the contractor furnishing such bond or bonds shall have a right of action upon the bond or bonds upon giving written notice to the contractor within four months from the date on which such person did or performed the last of the labor or furnished or supplied the last of the material for which such claim is made, stating with substantial accuracy the amount claimed and the name of the party to whom the material was furnished or supplied or for whom the labor was done or performed. Such notice shall be served by mailing the same by registered or certified mail, postage prepaid, in an envelope addressed to the contractor at any place he or she maintains an office or conducts his or her business or his or her residence or in any other manner in which a notice may be served.
Neb. Rev. Stat. §§ 52-118.01