Columbia subject headings:
Airplanes, Military.
Airplanes--Air refueling.
Harvard subject headings:
Airplanes, Military.
Airplanes--Air refueling
Airtankers (Military science)--United States.
United States. Air Force--Appropriations and expenditures.
Princeton subject headings:
Airtankers (Military science)--United States.
United States. Air Force--Appropriations and expenditures.