Neb. Rev. Stat. § 19-3325: Neb. Rev. Stat. § 19-3325

Proceedings under the Offstreet Parking District Act shall not be attacked after the hearing upon any grounds not stated in an objection or protest filed pursuant to the act. Any owner of real estate or person interested in any real estate within the district is estopped to attack the proceedings upon any ground not stated in the protest filed by him or her pursuant to the Offstreet Parking District Act.