ชัยเวชสกุล ย., and จิรวัฒน์กุล อ. “Reasons for Delayed Claiming of Inpatient Care in Sappasitthiprasong Hospital”. Journal of Health Science of Thailand, vol. 15, no. 6, Sept. 2021, pp. 903-12, https://www.thaidj.org/index.php/JHS/article/view/10767.