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Cairns BR, Collard MW, Landfear SM.Cairns BR, et al. Among authors: landfear sm.Proc Natl Acad Sci U S A. 1989 Oct;86(20):7682-6. doi: 10.1073/pnas.86.20.7682.Proc Natl Acad Sci U S A. 1989.PMID: 2813352Free PMC article.