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Ahearn JM, Hayward SD, Hickey JC, Fearon DT.Ahearn JM, et al.Proc Natl Acad Sci U S A. 1988 Dec;85(23):9307-11. doi: 10.1073/pnas.85.23.9307.Proc Natl Acad Sci U S A. 1988.PMID: 2848261Free PMC article.