RT Journal Article SR Electronic T1 Use of cluster analysis to define COPD phenotypes JF European Respiratory Journal JO Eur Respir J FD European Respiratory Society SP 472 OP 474 DO 10.1183/09031936.00035210 VO 36 IS 3 A1 M. Weatherall A1 P. Shirtcliffe A1 J. Travers A1 R. Beasley YR 2010 UL http://erj.ersjournals.com/content/36/3/472.abstract AB