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Berchner-Pfannschmidt U, Frede S, Wotzlaw C, Fandrey J.Berchner-Pfannschmidt U, et al. Among authors: frede s.Eur Respir J. 2008 Jul;32(1):210-7. doi: 10.1183/09031936.00013408.Eur Respir J. 2008.PMID: 18591338Free article.Review.