1. R. J. Briggs, Electron-Stream Interaction with Plasmas, Research Monograph No, 29, M.I.T. Press, Cambridge, Mass., 1964.
2. A. Bers. Linear Waves and Instabilities, in Physique des Plasmas, C. DeWitt & J. Peyraud (Ed.), Gordon & Breach, New York, 1975.
3. G. E. Mattingly & W. O. Criminale. J. Fluid Mech., 51, 233, 1972.
4. P. Huerre & P. A. Monkewitz. J. Fluid Mech., 159, 151, 1985.
5. AIAA Paper;PA Monkewitz,1986