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Sampson RJ, Sharkey P, Raudenbush SW.Sampson RJ, et al. Among authors: raudenbush sw.Proc Natl Acad Sci U S A. 2008 Jan 22;105(3):845-52. doi: 10.1073/pnas.0710189104. Epub 2007 Dec 19.Proc Natl Acad Sci U S A. 2008.PMID: 18093915Free PMC article.