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Warren RS, Donner DB, Starnes HF Jr, Brennan MF.Warren RS, et al.Proc Natl Acad Sci U S A. 1987 Dec;84(23):8619-22. doi: 10.1073/pnas.84.23.8619.Proc Natl Acad Sci U S A. 1987.PMID: 2825198Free PMC article.