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Charnock SJ, Brown IE, Turkenburg JP, Black GW, Davies GJ.Charnock SJ, et al. Among authors: turkenburg jp.Proc Natl Acad Sci U S A. 2002 Sep 17;99(19):12067-72. doi: 10.1073/pnas.182431199. Epub 2002 Sep 9.Proc Natl Acad Sci U S A. 2002.PMID: 12221284Free PMC article.