1. Bruce, R. S., Nature, 199, 1107 (1963).
2. Spencer, H., Menczel, J., and Samachson, J., Proc. Soc. Exp. Biol. and Med., 117, 59 (1964).
3. Volf, V., in Proc. Symp. on Some Aspects of Strontium Metabolism (Academic Press, 1967).
4. Skoryna, S. C., Paul, T. M., and Waldron-Edward, D., Canad. Med. Assoc. J., 91, 285 (1964); ibid., 93, 404 (1965).
5. Hesp, R., and Ramsbottom, B., Nature, 208, 1341 (1965).