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Olmsted JB, Witman GB, Carlson K, Rosenbaum JL.Olmsted JB, et al. Among authors: witman gb.Proc Natl Acad Sci U S A. 1971 Sep;68(9):2273-7. doi: 10.1073/pnas.68.9.2273.Proc Natl Acad Sci U S A. 1971.PMID: 5289385Free PMC article.