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Fraker PJ, DePasquale-Jardieu P, Zwickl CM, Luecke RW.Fraker PJ, et al.Proc Natl Acad Sci U S A. 1978 Nov;75(11):5660-4. doi: 10.1073/pnas.75.11.5660.Proc Natl Acad Sci U S A. 1978.PMID: 310122Free PMC article.