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Hawkins ED, Turner ML, Dowling MR, van Gend C, Hodgkin PD.Hawkins ED, et al. Among authors: hodgkin pd.Proc Natl Acad Sci U S A. 2007 Mar 20;104(12):5032-7. doi: 10.1073/pnas.0700026104. Epub 2007 Mar 14.Proc Natl Acad Sci U S A. 2007.PMID: 17360353Free PMC article.