1. Axelrod, J., and J. K. Inscoe: The uptake and binding of circulating serotonin and the effect of drugs. J. Pharmacol. exp. Ther. 141, 161?175 (1963).
2. Bogdanski, D. F., A. Pletscher, B. B. Brodie, and S. Udenfriend: Identification and assay of serotonin in brain. J. Pharmacol. exp. Ther. 117, 82?88 (1956).
3. Broadhurst, P. L., and S. Levine: Behavioral consistency in strains of rats selectively bred for emotional elimination. Brit. J. Psychol. 54, 121?125 (1963).
4. Buchel, L., J. Levy, and O. Tanguy: Sur la potentialisation de laction analgesique de la L-methadone par la 5-hydroxytryptamine (serotonine). C. R. Acad. Sci. (Paris) 246, 2947 (1958).
5. Costa, E.: The neuropharmacological background, antidepressant drugs, address at Amer. Psychiat. Assoc. Meeting, N. Y. C. (1965).