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Rader AJ, Hespenheide BM, Kuhn LA, Thorpe MF.Rader AJ, et al.Proc Natl Acad Sci U S A. 2002 Mar 19;99(6):3540-5. doi: 10.1073/pnas.062492699. Epub 2002 Mar 12.Proc Natl Acad Sci U S A. 2002.PMID: 11891336Free PMC article.