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Nijhuis BJ, Reinders-Messelink HA, de Blécourt AC, Olijve WG, Haga N, Groothoff JW, Nakken H, Postema K.Nijhuis BJ, et al.Child Care Health Dev. 2007 Sep;33(5):593-603. doi: 10.1111/j.1365-2214.2006.00719.x.Child Care Health Dev. 2007.PMID: 17725782