Petitions for improvements provided for in sections 14-384 to 14-3,127 after having been filed with the city shall not be returned or withdrawn, nor shall any person be allowed to add, cancel, erase, or withdraw or in any way modify any signature or writing on such petitions. Where two or more petitions are filed for the same improvement they shall be considered and taken together as one petition.
Neb. Rev. Stat. §§ 14-3,118