Cited 4 times since 2011 (0.3 per year) source: EuropePMC The European respiratory journal, Volume 37, Issue 4, 1 1 2011, Pages 960-962 Cardiac shunt in COPD as a cause of severe hypoxaemia: probably not so uncommon after all. Boerrigter BG, Boonstra A, Westerhof N, Postmus PE, Vonk-Noordegraaf A