Porprasit, Nujaree, Ann Jirapongsuwan, Surintorn Kalampakorn, and Sukhontha Siri. “Factors associated with quality of spirometry at occupational medicine clinic in Nopparat Rajathanee Hospital”. Journal of Medicine and Health Sciences 27, no. 3 (December 30, 2020): 69–82. accessed October 8, 2026. https://he01.tci-thaijo.org/index.php/jmhs/article/view/246817.