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Kohl NE, Emini EA, Schleif WA, Davis LJ, Heimbach JC, Dixon RA, Scolnick EM, Sigal IS.Kohl NE, et al. Among authors: schleif wa.Proc Natl Acad Sci U S A. 1988 Jul;85(13):4686-90. doi: 10.1073/pnas.85.13.4686.Proc Natl Acad Sci U S A. 1988.PMID: 3290901Free PMC article.