1. Schairer , G. S. September 1961 Looking ahead in V/STOL
2. Gerard , W. C. J. July 1960 V/STOL cargo airplane characteristics 60 69
3. The subsonic VTOL and GETOL in perspective;Stepniewski;Aerospace Engineering,April 1962
4. Moseh , H. C. Fay November 1961 Solution to the stall problem with a tiltwing aircraft