1. Mortimer, D., Sharp, W. B. A., and Holmes, D. R., Third Intern. Cong. Metallic Corr., Moscow (1966).
2. Barrett, C. A., Evans, E. B., and Baldwin, W. M., in Armed Services Tech. Inform. Agency Doc. No. AD 80836 (1955).
3. Mortimer, D., thesis, Univ. Manchester (1964).
4. Hagel, W. C., J. App. Phys., 36, 2596 (1965).
5. Fischer, W. A., and Lorenz, G., Arch. Eisenhuttenw., 28, 497 (1957).