(2008, March 14). Study aims to clear haze surrounding pot addiction. San Diego
Tanda, G., Pontieri, F.E., & Di Chiara, G. (1997, June 27). Cannabinoid and Heroin Activation of Mesolimbic Dopamine Transmission by a Common µ1 Opioid Receptor Mechanism. Science, 276, 2048 - 2050.
Vandrey, R.G., Budney, A.J., Hughes, J.R., & A. Liguori. (2008, January 1). A within-subject comparison of withdrawal symptoms during abstinence from cannabis, tobacco, and both substances.