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van den Berg JJ, Bock B, Roberts MB, Stein LA, Friedmann PD, Martin SA, Clarke JG.van den Berg JJ, et al. Among authors: stein la.Nicotine Tob Res. 2014 Feb;16(2):238-42. doi: 10.1093/ntr/ntt163. Epub 2013 Oct 22.Nicotine Tob Res. 2014.PMID: 24151140Free PMC article.