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Choi KH, Groarke JM, Young DC, Kuhn RJ, Smith JL, Pevear DC, Rossmann MG.Choi KH, et al. Among authors: kuhn rj.Proc Natl Acad Sci U S A. 2004 Mar 30;101(13):4425-30. doi: 10.1073/pnas.0400660101. Epub 2004 Mar 19.Proc Natl Acad Sci U S A. 2004.PMID: 15070734Free PMC article.