Helicopter Air Service Program: Hearings before the Aviation Subcommittee of the Committee on Commerce, United States Senate, Eighty-Ninth Congress, First Session on Helicopter Air Service Program, March 8-11, 1965, US Government (Washington, DC) Serial No. 89-4.
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New York Airways Collection, Acc. NASM.1992.0052, National Air and Space Museum, Smithsonian Institution.