1. Bläsig J, Herz A, Reinhold K, Zieglgansberger S (1973) Development of physical dependence on morphine in respect to time and dosage and quantification of the precipitated withdrawal syndrome in rats. Psychopharmacologia 33:19–38
2. Cochin J, Miller J, Roscow C, Grell R, Poulsen J (1979) The influence of the mode of morphine administration on tolerance and dependence. In: Harris L (ed) Problems of drug dependence (NIDA Research Monograph) 27:36–47. Superintendent of Documents, Washington, DC
3. D'Amour FE, Smith DL (1941) A method for determining loss of pain sensation. J Pharmacol Exp Ther 72:74–79
4. Gianutsos G, Hynes M, Drawbaugh R, Lal H (1975) Paradoxical absence of aggression during naloxone-precipitated morphine withdrawal. Psychopharmacologia 42:43–46
5. Gianutsos G, Hynes M, Lal H (1976) Enhancement of morphine-withdrawal and apomorphine-induced aggression by clonidine. Psychopharmacol Commun 2:165–171