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Tsai CL, Pan CY, Chang YK, Wang CH, Tseng KD.Tsai CL, et al.Res Dev Disabil. 2010 May-Jun;31(3):642-55. doi: 10.1016/j.ridd.2010.01.003. Epub 2010 Feb 16.Res Dev Disabil. 2010.PMID: 20163934