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Schneider JS, Stone MK, Wynne-Edwards KE, Horton TH, Lydon J, O'Malley B, Levine JE.Schneider JS, et al.Proc Natl Acad Sci U S A. 2003 Mar 4;100(5):2951-6. doi: 10.1073/pnas.0130100100. Epub 2003 Feb 24.Proc Natl Acad Sci U S A. 2003.PMID: 12601162Free PMC article.