1. Rhodin, T. N., Ann. N.Y. Acad. Sci., 58, 855 (1954).
2. Okamoto, G., Shibata, T., Ishikawa, T., and Nagayama, M., Extended Abstrs., Second Intern. Cong. Metallic Corrosion, New York, 50 (1963).
3. Unpublished results.
4. Carius, C., Arch. Eisenhüttenwes., 27, 401 (1956).