1. Siegmund, E., Cadmus, R., and Lu, G., Proc. Soc. Exp. Biol. and Med., 95, 729 (1957).
2. Hendershot, L. C., and Forsaith, J., J. Pharmacol. Exp. Ther., 125, 237 (1959).
3. Koster, R., Anderson, M., and de Beer, E. J., Fed. Proc., 18, 412 (1959).
4. Emele, J. F., Shanaman, J., and Warren, M. R., J. Pharmacol. Exp. Ther., 134, 206 (1961).
5. Brown, D. M., and Hughes, B. O., J. Pharm. Pharmacol., 14, 399 (1962).