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Zhu JL, Vestergaard M, Hjollund NH, Olsen J.Zhu JL, et al. Among authors: olsen j.Scand J Work Environ Health. 2006 Feb;32(1):61-6. doi: 10.5271/sjweh.977.Scand J Work Environ Health. 2006.PMID: 16539173Free article.