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Mayhew PJ, Bell MA, Benton TG, McGowan AJ.Mayhew PJ, et al.Proc Natl Acad Sci U S A. 2012 Sep 18;109(38):15141-5. doi: 10.1073/pnas.1200844109. Epub 2012 Sep 4.Proc Natl Acad Sci U S A. 2012.PMID: 22949697Free PMC article.