1. Rekker, R.F., Engel, D.J.C. and Nyes, G.G.:J. Pharm. Pharmacol. 24, 589 (1972).
2. Abdel-Moneim, M.M.:J. Med. Chem. 18, 427 (1975).
3. Kim, J.C., Cannon, J.G., Long, J.P. and Heintz, S.:ASPET Meeting, East Lansing, Mich., 1973, Abstract No. 129.
4. Long, J.P., Heintz, S., Cannon, J.G. and Kim, J.C.:J. Pharmacol. Exp. Ther. 129, 336 (1975).
5. Cannon, J.G. and Kim, J.C.:U.S. Patent, 347, 170 (June 27, 1974).