United States. General Accounting Office. Military Aircraft: Considerations in Reviewing the Air Force Proposal to Lease Aerial Refueling Aircraft, text, July 23, 2003; (https://digital.library.unt.edu/ark:/67531/metadc292631/m1/1/: accessed February 16, 2020), University of North Texas Libraries, UNT Digital Library, digital.library.unt.edu; .