Khiawwan, Supattra, and Theerasuk Kawamatawong. “Correlation of Composite Indices and COPD Assessment Test in Thai COPD Patients”. Ramathibodi Medical Journal 44, no. 3 (September 24, 2021): 29–40. Accessed May 4, 2024. https://he02.tci-thaijo.org/index.php/ramajournal/article/view/242498.