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Ohrt-Nissen S, Friis-Hansen L, Dahl B, Stensballe J, Romner B, Rasmussen LS.Ohrt-Nissen S, et al. Among authors: dahl b.Emerg Med J. 2011 Nov;28(11):941-4. doi: 10.1136/emj.2010.091363. Epub 2010 Oct 14.Emerg Med J. 2011.PMID: 20947920Free PMC article.