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Wallace JM Jr, Bachman JG, O'Malley PM, Schulenberg JE, Cooper SM, Johnston LD.Wallace JM Jr, et al. Among authors: johnston ld.Addiction. 2003 Feb;98(2):225-34. doi: 10.1046/j.1360-0443.2003.00282.x.Addiction. 2003.PMID: 12534428Free article.