Al Zahrani, Mohammad. “Effectiveness of TheraPEP Versus Conventional Breathing Techniques in Managing Acute COPD Exacerbations”. International Journal of Physical Therapy Research & Practice 3, no. 8 (September 30, 2024): 333–339. Accessed October 22, 2024. https://inkwellinfinite.com/index.php/ijprp/article/view/48.