Jansang, S. ., P. . Tungsukruthai, S. . Srisuma, K. . Sriyakul, A. . Krajarng, and S. . Kietinun. “Effect of Pursed-Lip Breathing Using a Windmill Toy Model on Breathing Efficiency in Chronic Obstructive Pulmonary Disease Patients”. Trends in Sciences, vol. 18, no. 23, Nov. 2021, p. 714, doi:10.48048/tis.2021.714.