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Park JH, Brown RL, Park CR, McCully K, Cohn M, Haselgrove J, Chance B.Park JH, et al.Proc Natl Acad Sci U S A. 1987 Dec;84(24):8976-80. doi: 10.1073/pnas.84.24.8976.Proc Natl Acad Sci U S A. 1987.PMID: 3480522Free PMC article.