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Forister ML, McCall AC, Sanders NJ, Fordyce JA, Thorne JH, O'Brien J, Waetjen DP, Shapiro AM.Forister ML, et al.Proc Natl Acad Sci U S A. 2010 Feb 2;107(5):2088-92. doi: 10.1073/pnas.0909686107. Epub 2010 Jan 19.Proc Natl Acad Sci U S A. 2010.PMID: 20133854Free PMC article.