Reankongngern, W., and C. . Samutwet. “The Development of a System for Online Appointment Referral Card in Outpatient Department, Omkoi Hospital”. Journal of Nursing and Public Health Research, vol. 2, no. 1, Apr. 2022, pp. 60-72, https://he02.tci-thaijo.org/index.php/jnphr/article/view/256154.