Duangjaras, N., and S. Chancharoen. “Developing of Damrongdhama Center Efficiency for Thailand Complaint Management Center in 4.0th”. Rajapark Journal, vol. 16, no. 44, Feb. 2022, pp. 267-79, https://so05.tci-thaijo.org/index.php/RJPJ/article/view/254252.