1. The Origin of Cosmic Rays
2. L. D. Landau and E. M. Lifshitz,Classical Theory of Fields(Addison-Wesley, Reading, Massachusetts, 1962), p. 128.
3. A. I. Morozov and L. S. Solovev, inReviews of Plasma Physics, edited by M. A. Leontovich (Consultants Bureau, New York, 1966), Vol. II, p. 203.
4. T. J. M. Boyd and J. J. Sanderson,Plasma Dynamics(Barnes and Noble, New York, 1969), p. 28.
5. Intensity effects in electron-laser interaction