Rodjanasingha, S. . “Prevalence and Risk Factors Associated With Readmission Within 28 Days of COPD Patients at Hua-Hin Hospital”. Hua Hin Medical Journal, vol. 2, no. 3, Jan. 2023, pp. 1-14, https://he01.tci-thaijo.org/index.php/hhsk/article/view/253760.