Alexis Droutzkoy books & textbook
American Helicopter - Magazine of Rotary Wings, Aviation, Airways, May 1948 (Ellehammer Model of 1912, Ramjets for Helicopters, Hangar Flying, Marquardt Jets)
G. F. Champlin Erik Hildes-Heim Allyn B. Hazard James H. Louie Corwin D. Denney Alexis Droutzkoy
American Helicopter Magazine, New York /1948T Single Issue Magazine / 28 Pages
