1. F. Lang, Continuously variable transmissions: an overview of CVT research past, present, and future, 21W 732 USA. 2000.
2. S. J. Crockett, Shiftless, continuously-aligning transmission, Patent of USA 4, 932, 928, Cl. F16H 47/08, U. S. Cl. 475/51; 475/47.1990.
3. I. V. Volkov, Method of automatic and continuous changes in the torque and speed of rotation of the output shaft depending on the resistance to motion and the device for its implementation, Description of the invention to the Russian patent RU 2 234 626 of 27.03. 2004.
4. Wide-range economical planetary disk variator;Gulia;Bull. Mech. Eng.,2005
5. Power transmission system comprising two sets of epicyclic gears;Harries;Patent of Great Britain GB2238090 (A),1991