1. G. T. HAHN and A. R. ROSENFIELD,Met. Trans. 6A (1975) 653.
2. J. S. SANTNER, ibid.9A (1978) 769.
3. R. E. ZINKHAN and J. H. DEDRICK, in ?Fracture?, Vol. 6 (Academic Press, New York, 1969) p. 350.
4. E. H. DIX, JR,Trans. ASM 42 (1950) 1057.
5. H. WESTENGEN, D. REISO and L. AURAN,Aluminium 56 (1980) 768.