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Chiu YH, Spiegelman D, Dockery DW, Garshick E, Hammond SK, Smith TJ, Hart JE, Laden F.Chiu YH, et al.Environ Health Perspect. 2011 Sep;119(9):1294-300. doi: 10.1289/ehp.1003199. Epub 2011 May 31.Environ Health Perspect. 2011.PMID: 21628108Free PMC article.