Dal Negro, Roberto W., Paola Turco, and Massimiliano Povero. “Patients’ Usability of Seven Most Used Dry-Powder Inhalers in COPD”. Multidisciplinary Respiratory Medicine 14, no. 1 (September 13, 2019). Accessed July 7, 2024. https://mrmjournal.org/index.php/mrm/article/view/29.