1. Kaley, G., and Weiner, R., in Prostaglandin Symp. of the Worcester Foundation for Experimental Biology (edit. by Ramwell, P. W., and Shaw, J. E.), 321 (Interscience, New York, 1968).
2. Kaley, G., and Weiner, R., Ann. NY Acad. Sci., 180, 338 (1971).
3. Willis, A. L., J. Pharm. Pharmacol., 21, 126 (1969).
4. Piper, P. J., and Vane, J. R., Nature, 223, 29 (1969).
5. Kaley, G., and Weiner, R., Nature (in the press).