1. A.H. Nayfeh, Perturbation Methods, Wiley, New York (1973).
2. D.D. Joseph, Stability of Fluid Motions. Vols. I and II, Springer, Berlin (1976).
3. V.I. Arnold, V.S. Afraimovich, Yu.S. Il’yashenko, and L.P. Shil’nikov, “Bifurcation Theory,” in: Advances in Science and Engineering. Topical Problems of Mathematics. Vol. 5 [in Russian], All-Union Institute of Science and Technical Information, Moscow (1986), p. 5.
4. R.G. Finucane and R.E. Kelly, “Onset of Stability in a Fluid Layer Heated Sinusoidally from Below,” Int. J. Heat Mass Transfer 19, 71 (1976).
5. E.N. Lorentz, “Deterministic Nonperodic Flow,” J. Atmos. Sci. 20, 130 (1963).