1. C. G. Bieber, Metals Eng. Quart. 1, 92 (1961).
2. C T. Sims, J. of Metals 18, 1119 (1966).
3. C. P. Sullivan and M. J. Donachie, Metals Eng. Quart. 7, 36 (1967).
4. G. P. Sabol and R. Stickler, Physica Status Solidi 35, 11 (1969).
5. R. F. Decker, Symposium on Steel Strengthening Mechanisms, Zurich, Switzerland, May 5 and 6 (1969).