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Gospodarowicz D, Moran JS.Gospodarowicz D, et al. Among authors: moran js.Proc Natl Acad Sci U S A. 1974 Nov;71(11):4584-8. doi: 10.1073/pnas.71.11.4584.Proc Natl Acad Sci U S A. 1974.PMID: 4531001Free PMC article.