%0 Journal Article
%B Int J Chron Obstruct Pulmon Dis
%D 2017
%G eng
%P 1457-1468
%R 10.2147/COPD.S130713
%T The effect of COPD severity and study duration on exacerbation outcome in randomized controlled trials.
%V 12
%1 https://www.ncbi.nlm.nih.gov/pubmed/28553098?dopt=Abstract