A randomized controlled trial to compare the efficacy and safety of glycopyrronium bromide + salmeterol/fluticasone and tiotropium bromide + salmeterol/fluticasone in chronic obstructive pulmonary disease. ijmhs [Internet]. 2020 May 25 [cited 2026 Oct. 23];10(05):853-7. Available from: http://www.innovativejournal.in/index.php/ijmhs/article/view/2917