Columbia subject headings:
Aeronautics, Commercial--United States.
Airlines--United States.
United States. Civil Aeronautics Board.
Harvard subject headings:
Aeronautics, Commercial--United States--Periodicals
United States. Civil Aeronautics Board--Periodicals.
Princeton subject headings:
Aeronautics, Commercial--United States--Periodicals.
Periodicals.
United States. Civil Aeronautics Board--Periodicals.