1. J.W. Dungey, Proceeding of the Ionosphere, The Physical Society of London, London, 1955, p. 255.
2. Interplanetary Dynamical Processes;Parker,1963
3. J.C. Brandt, D.A. Mendis, in: C.F. Kennel et al. (Eds.), Solar System Plasma Physics, Vol. 2, North-Holland, Amsterdam, 1979, p. 253.
4. Non-linear dispersion of water waves
5. Instability of periodic wavetrains in nonlinear dispersive systems