31 C.F.R. § 538.517 Allowable payments for overflights of Sudanese airspace.
Title 31 - Money and Finance: Treasury
Payments to Sudan of charges for services rendered by the Government of Sudan in connection with the overflight of Sudan or emergency landing in Sudan of aircraft owned by a United States person or registered in the United States are authorized.
Title 31: Money and Finance: Treasury
PART 538—SUDANESE SANCTIONS REGULATIONS
Subpart E—Licenses, Authorizations, and Statements of Licensing Policy
§ 538.517 Allowable payments for overflights of Sudanese airspace.

