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Karstadt M, Haseman JK.Karstadt M, et al.Am J Ind Med. 1997 May;31(5):485-94. doi: 10.1002/(sici)1097-0274(199705)31:5<485::aid-ajim1>3.0.co;2-t.Am J Ind Med. 1997.PMID: 9099349