Valli G, Paoletti P, Savi D, Martolini D, Palange P. Clinical use of Heliox in Asthma and COPD. Monaldi Arch Chest Dis [Internet]. 2016 Feb. 3 [cited 2024 Apr. 27];67(3). Available from: https://www.monaldi-archives.org/macd/article/view/488