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Zeytinoğlu FN, Gagel RF, Tashjian AH Jr, Hammer RA, Leeman SE.Zeytinoğlu FN, et al.Proc Natl Acad Sci U S A. 1980 Jun;77(6):3741-5. doi: 10.1073/pnas.77.6.3741.Proc Natl Acad Sci U S A. 1980.PMID: 6932046Free PMC article.