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Ostlund RE Jr, McGill JB, Herskowitz I, Kipnis DM, Santiago JV, Sherman WR.Ostlund RE Jr, et al. Among authors: sherman wr.Proc Natl Acad Sci U S A. 1993 Nov 1;90(21):9988-92. doi: 10.1073/pnas.90.21.9988.Proc Natl Acad Sci U S A. 1993.PMID: 8234346Free PMC article.