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Jung G, Korn ED, Hammer JA 3rd.Jung G, et al. Among authors: korn ed.Proc Natl Acad Sci U S A. 1987 Oct;84(19):6720-4. doi: 10.1073/pnas.84.19.6720.Proc Natl Acad Sci U S A. 1987.PMID: 3477803Free PMC article.