1. Japan Patent 01-316399;Eisai Company, Ltd.,1989
2. J. Neurochem;Checler,1985
3. Ann. N. Y. Acad. Sci;Nemeroff,1988
4. Prog. Neuro-Psychopharmacol. Biol. Psychiatry;Ervin,1989
5. Yamakawa. I.: Tsushima. Y.: Machida. R.: Watanabe. S. J. Pharm. Sci., in press.