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Trisler GD, Schneider MD, Nirenberg M.Trisler GD, et al.Proc Natl Acad Sci U S A. 1981 Apr;78(4):2145-9. doi: 10.1073/pnas.78.4.2145.Proc Natl Acad Sci U S A. 1981.PMID: 6166002Free PMC article.