1. Minimum induced power requirements for flapping flight
2. TennekesH., The Simple Science of Flight, Revised and Expanded Edition: From Insects to Jumbo Jets, MIT Press, Cambridge, MA, 2009, p. 37.
3. KerrebrockJ. L., Aircraft Engines and Gas Turbines, 2nd ed., MIT Press, Cambridge, MA, 1992, pp. 464–466.