Section 213.4 - Sale of oil and gas leases(a) At such times and in such manner as he may deem appropriate, the Area Director shall publish notices at least thirty days prior to the sale, unless a shorter period is authorized by the Commissioner of Indian Affairs, that oil and gas leases on specific tracts, each of which shall be in a reasonably compact body, will be offered to the highest responsible bidder for a bonus consideration, in addition to stipulated rentals and royalties. Each bid must be accompanied by a cashier's check, certified check, or postal money order, payable to the payee designated in the invitation to bid, in an amount not less than 25 percent of the bonus bid. Within 30 days after notification of being the successful bidder, said bidder must remit the balance of the bonus, the first year's rental, and his share of the advertising costs, and shall file with the Area Director the lease in completed form. The Area Director may, for good and sufficient reasons, extend the time for the completion and submission of the lease form, but no extension shall be granted for remitting the balance of monies due. If the successful bidder fails to pay the full consideration within said period, or fails to file the completed lease within said period or extension thereof, or if the lease is disapproved through no fault of the lessor or the Department of the Interior, 25 percent of the bonus bid will be forfeited for the use and benefit of the Indian lessor.(b) In cases where any part of the bonus bid for a lease is paid directly to the Indian lessor, upon his signing the lease, the lessee must procure and file with the lease an affidavit of the lessor, sworn to before a U.S. Commissioner, Postmaster, Area Director, local representative of the Area Director, county or district judge, Federal judge or clerk of a Federal court, showing the amount of bonus so paid, and the balance thereof must be paid into the office of the Area Director upon filing the lease. Where possible lessees are requested to take the lessor to the nearest United States field clerk who will render all proper assistance in the execution of leases, and before whom the bonus affidavit may be executed in cases where any part of bonus consideration is paid directly to the lessor. Where leases are executed by guardians, under order of court, the affidavit of lessor may be executed before a notary public.(c) All notices or advertisements of sales of oil and gas leases shall reserve to the Secretary of the Interior the right to reject all bids when in his judgment the interests of the Indians will be best served by so doing, and that if no satisfactory bid is received, or if the accepted bidder fails to complete the lease or if the Secretary of the Interior shall determine that it is unwise in the interests of the Indians to accept the highest bid, the Secretary may readvertise such lease for sale, or if deemed advisable, with the consent of the Indian owners, a lease may be made by private negotiations. The successful bidder or bidders will be required to pay his or their share of the advertising costs. Amounts received from unsuccessful bidders will be returned; but when no bid is accepted on a tract, the costs of advertising will be assessed against the applicant who requested that said tract be advertised. Secs. 16, 17, 48 Stat. 987, 988, sec. 9, 49 Stat. 1968, sec. 4, 52 Stat. 348; 25 U.S.C. 396d , 476 , 477 , 509