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Ballard E, McDonnell L, Keilty S, Davidson AC, Hart N; British Thoracic Society Respiratory Critical Care Specialist Advisory Group.Ballard E, et al. Among authors: davidson ac.Thorax. 2011 Sep;66(9):823-4. doi: 10.1136/thx.2010.143669. Epub 2010 Oct 11.Thorax. 2011.PMID: 20937644No abstract available.