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Fritz-Wolf K, Becker A, Rahlfs S, Harwaldt P, Schirmer RH, Kabsch W, Becker K.Fritz-Wolf K, et al. Among authors: rahlfs s.Proc Natl Acad Sci U S A. 2003 Nov 25;100(24):13821-6. doi: 10.1073/pnas.2333763100. Epub 2003 Nov 17.Proc Natl Acad Sci U S A. 2003.PMID: 14623980Free PMC article.