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Williams WV, Moss DA, Kieber-Emmons T, Cohen JA, Myers JN, Weiner DB, Greene MI.Williams WV, et al.Proc Natl Acad Sci U S A. 1989 Jul;86(14):5537-41. doi: 10.1073/pnas.86.14.5537.Proc Natl Acad Sci U S A. 1989.PMID: 2501789Free PMC article.