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Fawcett JW, O'Leary DD, Cowan WM.Fawcett JW, et al. Among authors: cowan wm.Proc Natl Acad Sci U S A. 1984 Sep;81(17):5589-93. doi: 10.1073/pnas.81.17.5589.Proc Natl Acad Sci U S A. 1984.PMID: 6591206Free PMC article.
O'Leary DD, Cowan WM.O'Leary DD, et al. Among authors: cowan wm.Proc Natl Acad Sci U S A. 1983 Oct;80(19):6131-5. doi: 10.1073/pnas.80.19.6131.Proc Natl Acad Sci U S A. 1983.PMID: 6193529Free PMC article.