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Smythe JA, Coppel RL, Day KP, Martin RK, Oduola AM, Kemp DJ, Anders RF.Smythe JA, et al. Among authors: kemp dj.Proc Natl Acad Sci U S A. 1991 Mar 1;88(5):1751-5. doi: 10.1073/pnas.88.5.1751.Proc Natl Acad Sci U S A. 1991.PMID: 2000383Free PMC article.