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Edgcomb VP, Kysela DT, Teske A, de Vera Gomez A, Sogin ML.Edgcomb VP, et al.Proc Natl Acad Sci U S A. 2002 May 28;99(11):7658-62. doi: 10.1073/pnas.062186399.Proc Natl Acad Sci U S A. 2002.PMID: 12032339Free PMC article.