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McArdle N, Grove A, Devereux G, Mackay-Brown L, Mackay T, Douglas NJ.McArdle N, et al.Eur Respir J. 2000 Apr;15(4):670-5. doi: 10.1034/j.1399-3003.2000.15d08.x.Eur Respir J. 2000.PMID: 10780757Free article.Clinical Trial.