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2. D.H. Hodges, R.A. Ormiston, Stability of elastic bending and torsion of uniform cantilever blades in hover with variable structural coupling, NASA, TN D-8192, 1976.
3. A. Rosen, P.P. Friedmann, Non-linear equations of equilibrium for elastic helicopter or wind turbine blades undergoing moderate deflection, NASA, CR 159478, October 1978.
4. The non-linear behavior of elastic slender straight beams undergoing small strains and moderate deflections;Rosen;J. Appl. Mech.,1979
5. J. Shamie, P.P. Friedmann, Effect of moderate deflections on the aeroelastic stability of a rotor blade in forward flight, Proceedings of the Third European Rotorcraft and Powered Lift Aircraft Forum Aix-en Provence, France, 1977, pp. 24.1–24.37.