All orders of the Board, following the close of any contested hearing shall be transmitted to-the parties of record by certified mail. All other orders will be sent by regular course of mail. Motion for rehearing shall be filed within ten (10) days after the date of mailing a copy of the order by the Board to the party appealing and shall comply with Section 75-137(2), R. R. S., 1943, as amended.
285 Neb. Admin. Code, ch. 3, § 020