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Safer B, Adams SL, Kemper WM, Berry KW, Lloyd M, Merrick WC.Safer B, et al. Among authors: kemper wm.Proc Natl Acad Sci U S A. 1976 Aug;73(8):2584-8. doi: 10.1073/pnas.73.8.2584.Proc Natl Acad Sci U S A. 1976.PMID: 1066667Free PMC article.