Supakdee, K., P. Suansokchuak, K. Pranet, and T. Khotmongkol. “A Development of Model for School Milk’s Transportation Vehicles in Ubon Ratchathani and Sisaket Provinces”. Thai Industrial Engineering Network Journal, vol. 5, no. 1, June 2019, pp. 59-65, https://ph02.tci-thaijo.org/index.php/ienj/article/view/188618.