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Kroll SD, Omri G, Landau EM, Iyengar R.Kroll SD, et al. Among authors: landau em.Proc Natl Acad Sci U S A. 1991 Jun 15;88(12):5182-6. doi: 10.1073/pnas.88.12.5182.Proc Natl Acad Sci U S A. 1991.PMID: 1828893Free PMC article.