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Conway DJ, Roper C, Oduola AM, Arnot DE, Kremsner PG, Grobusch MP, Curtis CF, Greenwood BM.Conway DJ, et al. Among authors: roper c.Proc Natl Acad Sci U S A. 1999 Apr 13;96(8):4506-11. doi: 10.1073/pnas.96.8.4506.Proc Natl Acad Sci U S A. 1999.PMID: 10200292Free PMC article.