[21] Letter, Clarence H. Wiegman to National Air Museum, November 1, 1961.
[22] Letter, Dorner to National Air Museum, January 15, 1962.
[23] Letter, Hugo T. Byttebier to National Air Museum, October 20, 1961.
[24] Letter, Clarence D. Chamberlin to National Air Museum, February 8, 1964.
[25] Ruth Nichols, Wings For Life (Philadelphia and New York: J. B. Lippincott Co., 1957), p. 205.
[26] Letter, Richard Totten to National Air Museum, January 28, 1964.
[27] Letter, Richard Totten to National Air Museum, January 28, 1961.
[28] Aero Digest (February 1931), vol. 18, no. 2, p. 58.
[29] “50-Hour Test of Packard Diesel Aircraft Engine,” Packard Motor Car Company, Detroit, Michigan, serial no. 426, test no. 234-73, February 19, 1930.
[30] Blower in this sense refers to a low-pressure air pump (supercharger) designed to increase cylinder scavenging efficiency by blowing out exhaust gasses. In doing this it also increases somewhat the amount of fresh air introduced into the cylinders. Woolson invented a 2-stroke cycle blown engine; the patent was issued in 1932 (patent 1853714) with rights assigned to the Packard Motor Car Company. (Woolson himself died in 1930.)