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Burton EA, Tinsley JM, Holzfeind PJ, Rodrigues NR, Davies KE.Burton EA, et al. Among authors: davies ke.Proc Natl Acad Sci U S A. 1999 Nov 23;96(24):14025-30. doi: 10.1073/pnas.96.24.14025.Proc Natl Acad Sci U S A. 1999.PMID: 10570192Free PMC article.