Butorphanol (Stadol) :A Study in Problems of Current Drug Information and Control
Neurol 48:1156-1160, Fisher,M.A.&Glass,S., 1997
Abrupt Outpatient Withdrawal of Medication in Analgesic-Abusing Migraineurs
Lancet 337:1442-1443, Hering,T.&Steiner,T.J., 1991
Adult Menengoencephalitis caused by Herpes virus Hominis type 2
Am J Med 56:540, Morrison,R.E., 1974