TY  - RPRT
TI  - Chronic obstructive pulmonary disease.
AU  - P M A Calverley
AU  - Paul Walker
PY  - 2003
DO  - 10.1016/s0140-6736(03)14416-9
UR  - https://pubmed.ncbi.nlm.nih.gov/14522537/
ID  - 14522537
ER  -