Molino A, Simioli F, Stanziola AA, Mormile M, Martino M, D’Amato M. Effects of combination therapy indacaterol/ glycopyrronium versus tiotropium on moderate to severe COPD: evaluation of impulse oscillometry and exacerbation rate. Multidiscip Respir Med. 2017;12(1). doi:10.4081/mrm.2017.250