TY  - RPRT
TI  - [Understanding clinical trials in COPD].
AU  - P Calverley
PY  - 2005
DO  - 10.1016/s0761-8425(05)85605-0
UR  - https://pubmed.ncbi.nlm.nih.gov/16294172/
ID  - 16294172
ER  -