Except to prevent loss or waste, leases on undivided inherited lands will not be approved until the heirship determination has been approved. If the heirs to undivided inherited lands are undetermined or cannot be located, or if the heirs owning less than one-half interest in the lands refuse to sign a lease and it appears necessary to lease the lands to prevent loss or waste, the Area Director will report the facts to the Commissioner of Indian Affairs and ask for instructions. Minor heirs can lease or joint adult heirs in leasing only through guardians under order of court. Proof of heirship shall be given upon Form F prescribed. If probate or other court proceedings have established the heirship in any case, or the land has been partitioned, certified copy of final order, judgment, or decree of the court will be accepted in lieu of Form F.