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Van der Vijver LP, van der Waal MA, Weterings KG, Dekker JM, Schouten EG, Kok FJ.Van der Vijver LP, et al. Among authors: dekker jm.Int J Epidemiol. 1992 Feb;21(1):36-9. doi: 10.1093/ije/21.1.36.Int J Epidemiol. 1992.PMID: 1544755