1. Lightfoot, R. B., “CAA Testing of Helicopter,” presented at the Annual Meeting of the Institute of the Aeronautical Sciences, January, 1947.
2. CAA Flight Engineering Report No. 17, “The Apparent Effect of Pilot Technique and Atmospheric Disturbances upon the Measured Rate of Climb of an Airplane.”
3. “Ground Vibrations of Helicopters,”;Deutsch;Journal of the Aeronautical Sciences,1946
4. “Vibrations of Helicopters on the Ground,”;Horvay;Journal of the Aeronautical Sciences,1946
5. Meyers, Gary, C. Jr., “Flight Measurements of Helicopter Blade Motion with a Comparison Between Theoretical and Experimental Results,” NACA Technical Note 265, April, 1947.