RT Journal Article SR Electronic T1 Global burden of COPD: systematic review and meta-analysis JF European Respiratory Journal JO Eur Respir J FD European Respiratory Society DO 10.1183/09031936.06.00124605 A1 R.J. Halbert A1 J.L. Natoli A1 Anacleto Gano A1 E. Badamgarav A1 A.S. Buist A1 D.M. Mannino YR 2006 UL http://erj.ersjournals.com/content/early/2006/04/12/09031936.06.00124605.abstract AB