Author's amendment and updating list, 28 July 1993, for Woodman, Harry, Early Aircraft Armament: The Aeroplane and the Gun up to 1918, since published as Williams, Anthony G. and Emmanuel Gustin, Flying Guns World War I: Development of Aircraft Guns, Ammunition and Installations 1914-32, Marlborough, Wiltshire, United Kingdom: Crowood Press, 2003, ISBN1-84037-396-2.