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Matson JL, LoVullo SV.Matson JL, et al. Among authors: lovullo sv.Res Dev Disabil. 2009 Jul-Aug;30(4):799-807. doi: 10.1016/j.ridd.2008.12.001. Epub 2009 Jan 21.Res Dev Disabil. 2009.PMID: 19162439Review.