1. R. PISHKO, M. McKIMPSON and P. G. SHEWMON,Met. Trans. 10A (1979) 887.
2. P. FELTHAM and M. A. EVANS, in ?Proceedings of 4th International Conference on the Strength of Metals and Alloys?, Nancy, France, 30 August to 3 September 1976, Vol. 3, p. 1235.
3. M. Z. BUTT and P. FELTHAM,Fizika 14 (1982) in press.
4. J. P. HIRTH,Res. Mech. Lett. 1 (1981) 3.
5. B. F. DYSON and M. J. RODGERS,ICF4,2 (University of Waterloo Press, 1977) p. 621.