O'Loughlin J, O'Loughlin EK, Wellman RJ, Sylvestre MP, Dugas EN, Chagnon M, Dutczak H, Lagu? J, McGrath JJ. Predictors of Cigarette Smoking Initiation in Early, Middle, and Late Adolescence. J Adolesc Health. 2017 Sep; 61(3):363-370.