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Seppä VP, Pelkonen AS, Kotaniemi-Syrjänen A, Viik J, Mäkelä MJ, Malmberg LP.Seppä VP, et al.Eur Respir J. 2016 Jun;47(6):1687-96. doi: 10.1183/13993003.00989-2015. Epub 2016 Mar 17.Eur Respir J. 2016.PMID: 26989106Free article.