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Frei A, Svarin A, Steurer-Stey C, Puhan MA.Frei A, et al.Health Qual Life Outcomes. 2009 Sep 26;7:86. doi: 10.1186/1477-7525-7-86.Health Qual Life Outcomes. 2009.PMID: 19781095Free PMC article.Review.
Steurer-Stey C, Dalla Lana K, Braun J, Ter Riet G, Puhan MA.Steurer-Stey C, et al.Eur Respir J. 2018 Jan 4;51(1):1701375. doi: 10.1183/13993003.01375-2017. Print 2018 Jan.Eur Respir J. 2018.PMID: 29301921Free article.