Neb. Rev. Stat. § 25-1902 : COURTS; CIVIL PROCEDURE — REVERSAL OR MODIFICATION OF JUDGMENTS AND ORDERS BY APPELLATE COURTS —REVIEW ON PETITION IN ERROR —1902 - Final order, defined; appeal
(1) The following are final orders which may be vacated, modified, or reversed:
(a) An order affecting a substantial right in an action, when such order in effect determines the action and prevents a judgment;
(b) An order affecting a substantial right made during a special proceeding;
(c) An order affecting a substantial right made on summary application in an action after a judgment is entered; and
(d) An order denying a motion for summary judgment when such motion is based on the assertion of sovereign immunity or the immunity of a government official.
(2) An order under subdivision (1)(d) of this section may be appealed pursuant to section
25-1912 within thirty days after the entry of such order or within thirty days after the entry of judgment.