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Coenen S, Welschen I, Van Royen P, Kuyvenhoven MM, Denekens J, Verheij TJ.Coenen S, et al.Eur J Gen Pract. 2004 Dec;10(4):152-6. doi: 10.3109/13814780409044303.Eur J Gen Pract. 2004.PMID: 15724125Free article.