Neb. Rev. Stat. §§ 76-2,103
If by reason of a possibility of reverter created more than thirty years prior to May 15, 1959, a reverter has come into existence prior to May 15, 1959, no person shall commence an action for the recovery of the land or any part thereof based upon such possibility of reverter, after one year from May 15, 1959.
If by reason of a breach of a condition subsequent created more than thirty years prior to May 15, 1959, a right of reentry has come into existence prior to May 15, 1959, no person shall commence an action for the recovery of the land or any part thereof based upon such right of entry or reentry after one year from May 15, 1959, unless entry or reentry has been actually made to enforce said right before the expiration of such year.
Neb. Rev. Stat. §§ 76-2,103