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Rabosky DL, Glor RE.Rabosky DL, et al.Proc Natl Acad Sci U S A. 2010 Dec 21;107(51):22178-83. doi: 10.1073/pnas.1007606107. Epub 2010 Dec 6.Proc Natl Acad Sci U S A. 2010.PMID: 21135239Free PMC article.