Olapiriyakul, S., and T. Phohom. “Simulation modeling and analysis of the outpatient clinic of the college of medicine and public health, Ubon Ratchathani university”. Asia-Pacific Journal of Science and Technology, vol. 19, no. 1, Apr. 2017, pp. 82-91, https://so01.tci-thaijo.org/index.php/APST/article/view/82901.