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Duke JC, Vallone DM, Allen JA, Cullen J, Mowery PD, Xiao H, Dorrler N, Asche ET, Healton C.Duke JC, et al. Among authors: vallone dm.Am J Public Health. 2009 Dec;99(12):2210-6. doi: 10.2105/AJPH.2008.155127. Epub 2009 Oct 15.Am J Public Health. 2009.PMID: 19833994Free PMC article.