Author D. Groves U. Karsanji R. Evans N. Greening S. Singh J. Quint H. Whittaker M. Richardson J. Barrett S. Sutch M. Steiner Year of Publication 2021 DOI 10.2147/copd.s303202 DOIGoogle ScholarBibTeXEndNote X3 XMLEndNote 7 XMLEndnote taggedMarcRIS