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Carter RI, Mumford RA, Treonze KM, Finke PE, Davies P, Si Q, Humes JL, Dirksen A, Piitulainen E, Ahmad A, Stockley RA.Carter RI, et al. Among authors: davies p.Thorax. 2011 Aug;66(8):686-91. doi: 10.1136/thx.2010.154690. Epub 2011 May 26.Thorax. 2011.PMID: 21617168Clinical Trial.