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Graves DT, Owen AJ, Williams SR, Antoniades HN.Graves DT, et al.Proc Natl Acad Sci U S A. 1986 Jul;83(13):4636-40. doi: 10.1073/pnas.83.13.4636.Proc Natl Acad Sci U S A. 1986.PMID: 3460062Free PMC article.