Okla. Stat. tit. 58, § 58-903: Hearings in district court - Terms of sale

The district court shall establish a date upon which all

petitions for the approval of deeds to lands inherited by full-blood

Indians shall be heard which date shall be at least twice per month.

At a hearing the court shall take the testimony of disinterested

parties to establish the value of the lands to be conveyed, and may

in its discretion call in any United States probate attorney as

counsel for grantor. The attendance of the grantor or any other

person to testify in such matters may be required in like manner as

if his testimony were to be heard in a civil action. The court may

decline to approve any deed when in his judgment the price is not

commensurate with his fair judgment and the grantor is not an heir

of deceased. Provided, the district court may authorize the sale

and conveyance of any such land for cash or one-fourth (1/4) cash

and the balance in yearly payments of one-fourth (1/4) each, with

interest on such deferred payments at the rate of not less than six

percent (6%) per annum; Provided further, that in all sales upon

deferred payments such payments shall be secured by first mortgage

upon the lands conveyed.