1. ‘Coupled-mode instabilities in velocity saturated semiconductors’, ELAB report, AE-99, Norwegian Institute of Technology, Electronics Research Laboratory, Trondheim, Norway, 1968
2. Abramovitz, M., Stegun, I.A., Handbook of mathematical functions, Dover 1965), p. 232
3. ‘Instabilities due to velocity saturation in bulk regions of semiconductors’, University College London research report, 1969