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Edvardsen A, Akerø A, Hardie JA, Ryg M, Eagan TM, Skjønsberg OH, Bakke PS.Edvardsen A, et al. Among authors: hardie ja.Respir Med. 2011 Jan;105(1):50-6. doi: 10.1016/j.rmed.2010.10.006. Epub 2010 Oct 25.Respir Med. 2011.PMID: 20974527Free article.