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Heizmann O, Viehl CT, Schmid R, Müller-Brand J, Müller B, Oertli D.Heizmann O, et al.Eur J Med Res. 2009 Jan 28;14(1):37-41. doi: 10.1186/2047-783x-14-1-37.Eur J Med Res. 2009.PMID: 19258209Free PMC article.