1. See, for example, A. van der Ziel, Solid State Physical Electronics Chaps. 12 and 13. Prentice- Hall, Englewood Cliffs (1957).
2. S. Poganski, Halbleiterprobleme I (Ed. by W. Schottky) p. 275. Friedr. Vieweg, Braunschweig (1954).
3. W. SHockley, U.S. Pat. 2,569, 347.
4. H. Krömer, Proc. I.R.E. 45, 1535 (1957).
5. D. A. Jenny, Proc. I.R.E. 45, 959 (1957).