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Besansky NJ, Powell JR, Caccone A, Hamm DM, Scott JA, Collins FH.Besansky NJ, et al. Among authors: powell jr.Proc Natl Acad Sci U S A. 1994 Jul 19;91(15):6885-8. doi: 10.1073/pnas.91.15.6885.Proc Natl Acad Sci U S A. 1994.PMID: 8041714Free PMC article.