1. Scholes, G., Stein, G., and Weiss, J., Nature, 164, 709 (1949).
2. Weiss, J., Nature, 153, 748 (1944); Trans. Farad. Soc., 43, 314 (1947); Brit. J. Rad., Supp. 1, 56 (1947).
3. Limperos, G., and Moscher, W. A., Amer. J. Roent. and Rad. Ther., 63, No. 5, 681, 691 (1950).
4. Butler, J. A. V., and Smith, K. A., Nature, 165, 847 (1950).
5. Taylor, B., Greenstein, J. P., and Hollaender, A., Arch. Biochem., 16, 19 (1948).