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Craig SE, Kohler M, Nicoll D, Bratton DJ, Nunn A, Davies R, Stradling J.Craig SE, et al.Thorax. 2012 Dec;67(12):1090-6. doi: 10.1136/thoraxjnl-2012-202178. Epub 2012 Oct 30.Thorax. 2012.PMID: 23111478Clinical Trial.