1. Krauskopf, K. B., Geochim. Cosmochim. Acta, 9, 1 (1956).
2. Goldberg, E. D., in Chemical Oceanography (edit. by Riley, J. P., and Skirrow, G.), 1, 163 (Academic Press, London, 1965).
3. Chow, J. T., and Goldberg, E. D., Geochim. Cosmochim. Acta, 20, 192 (1960).
4. Turekian, K. K., and Johnson, D. G., Geochim. Cosmochim. Acta, 30, 1153 (1966).
5. Spitsyn, V. I., Torchenkova, E. A., and Glazkova, I. N., Dokl. Akad. Nauk SSSR, 133, 1111 (1960).