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Posada D, Crandall KA.Posada D, et al. Among authors: crandall ka.Proc Natl Acad Sci U S A. 2001 Nov 20;98(24):13757-62. doi: 10.1073/pnas.241370698.Proc Natl Acad Sci U S A. 2001.PMID: 11717435Free PMC article.