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Shaheen SO, Northstone K, Newson RB, Emmett PM, Sherriff A, Henderson AJ.Shaheen SO, et al.Thorax. 2009 May;64(5):411-7. doi: 10.1136/thx.2008.104703. Epub 2009 Feb 12.Thorax. 2009.PMID: 19213776
Greenough A, Shaheen SO, Shennan A, Seed PT, Poston L.Greenough A, et al. Among authors: shaheen so.Thorax. 2010 Nov;65(11):998-1003. doi: 10.1136/thx.2010.139915. Epub 2010 Oct 1.Thorax. 2010.PMID: 20889523Clinical Trial.