Srithawong, Arunrat, Puttipong Poncumhak, Sirintip Kumfu, and Tichanon Promsrisuk. 2019. “Predictive Equations for Peak Cough Flow in Healthy Senior Persons”. Srinagarind Medical Journal 34 (5):503-8. https://li01.tci-thaijo.org/index.php/SRIMEDJ/article/view/217552.