Neb. Rev. Stat. § 21-269

(MBCA 7.27) (a) The articles of incorporation may provide for a greater quorum or voting requirement for shareholders, or voting groups of shareholders, than is provided for by the Nebraska Model Business Corporation Act. (b) An amendment to the articles of incorporation that adds, changes, or deletes a greater quorum or voting requirement must meet the same quorum requirement and be adopted by the same vote and voting groups required to take action under the quorum and voting requirements then in effect or proposed to be adopted, whichever is greater.