1. D. McLean and L. Northcott, J. Iron Steel Inst. 158 (1948) 169.
2. W. Steven and K. Balajiva, ibid. 193 (1959) 141.
3. P. W. Palmberg and H. L. Marcus, Trans. ASM 62 (1969) 1016.
4. A. Joshi and D. F. Stein, STP499 (ASTM) (1972) 59.
5. Idem, J. Inst. Metals 99 (1971) 178.