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Hastings RP, Beck A, Daley D, Hill C.Hastings RP, et al. Among authors: daley d.Res Dev Disabil. 2005 Sep-Oct;26(5):456-68. doi: 10.1016/j.ridd.2004.10.003. Epub 2004 Dec 15.Res Dev Disabil. 2005.PMID: 16168883