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Levin DE, Bishop JM.Levin DE, et al. Among authors: bishop jm.Proc Natl Acad Sci U S A. 1990 Nov;87(21):8272-6. doi: 10.1073/pnas.87.21.8272.Proc Natl Acad Sci U S A. 1990.PMID: 2236039Free PMC article.
Levin DE, Hammond CI, Ralston RO, Bishop JM.Levin DE, et al. Among authors: bishop jm.Proc Natl Acad Sci U S A. 1987 Sep;84(17):6035-9. doi: 10.1073/pnas.84.17.6035.Proc Natl Acad Sci U S A. 1987.PMID: 2957690Free PMC article.