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Roelen CA, Koopmans PC, de Graaf JH, van Zandbergen JW, Groothoff JW.Roelen CA, et al.Occup Med (Lond). 2007 Oct;57(7):499-504. doi: 10.1093/occmed/kqm065. Epub 2007 Jul 23.Occup Med (Lond). 2007.PMID: 17646212