1. Horn, M. H., Teal, J. M., and Backus, R. H., Science, N.Y., 168, 245 (1970).
2. Polekarpov, G. G., Yegorov, V. N., Ivanov, V. N., Tokareva, A. V., and Feleppov, I. A., Priroda, No. 11 (1971).
3. Herring, P. J., J. mar. Biol. Assoc. U.K., 49, 766 (1969).
4. Conover, R. J., J. Fish. Res. Bd. Can., 28, 1327 (1971).
5. International Petroleum Encyclopedia (Petroleum Publishing Co., Tulsa, Oklahoma), 18 (1972).