W. Yu, F. Lemmer, D. Schlipf, and P. Cheng. The Science of Making Torque from Wind (TORQUE 2020), 1618, 2, page 022066. Institute of Physics Publishing, (2020)
K. Müller, and P. Cheng. Proceedings Of The ASME 37th International Conference on Ocean, Offshore and Arctic Engineering, 10 : Ocean Renewable Energy, page OMAE2018-78219, V010T09A065. New York, NY, ASME, (2018)