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Wyman PA, Brown CH, LoMurray M, Schmeelk-Cone K, Petrova M, Yu Q, Walsh E, Tu X, Wang W.Wyman PA, et al.Am J Public Health. 2010 Sep;100(9):1653-61. doi: 10.2105/AJPH.2009.190025. Epub 2010 Jul 15.Am J Public Health. 2010.PMID: 20634440Free PMC article.Clinical Trial.