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Rowe T, Rich TH, Vickers-Rich P, Springer M, Woodburne MO.Rowe T, et al.Proc Natl Acad Sci U S A. 2008 Jan 29;105(4):1238-42. doi: 10.1073/pnas.0706385105. Epub 2008 Jan 23.Proc Natl Acad Sci U S A. 2008.PMID: 18216270Free PMC article.