Okla. Stat. tit. 12, § 12-617: Reference in vacation

A judge, in vacation, upon the written consent of the parties,

may make an order of reference which the court of which he is a

member could make in term time. In such case, the order of

reference shall be made on the written agreement of the parties to

refer, and shall be filed with the clerk of the court, with the

other papers in the case.