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Rapp F, Butel JS, Melnick JL.Rapp F, et al. Among authors: butel js.Proc Natl Acad Sci U S A. 1965 Sep;54(3):717-24. doi: 10.1073/pnas.54.3.717.Proc Natl Acad Sci U S A. 1965.PMID: 4286418Free PMC article.No abstract available.