1. Toksöz, M. N., Press, F., Anderson, K., Dainty, A., Latham, G., Ewing, M., Dorman, J., Lammlein, D., Sutton, G., bier, F., and Nakamura, Y., Science, 176, 1012 (1972).
2. Gold, T., and Soter, S., Science, 169, 1071 (1970).
3. Jones, B. W., Proc. Third Lunar Sci. Conf., 3 (in the press).
4. Warren, N., Schreiber, E., Scholz, C., Morrison, J. A., Norton, P. R., Kumazawa, M., and Anderson, O. L., Proc. Second Lunar Sci. Conf., 3, 2345 (1971).
5. Rossi, R. C., and Fulrath, F. M., J. Amer. Cer. Soc., 48, 558 (1965).