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Firestein GS, Echeverri F, Yeo M, Zvaifler NJ, Green DR.Firestein GS, et al.Proc Natl Acad Sci U S A. 1997 Sep 30;94(20):10895-900. doi: 10.1073/pnas.94.20.10895.Proc Natl Acad Sci U S A. 1997.PMID: 9380731Free PMC article.