เลียงจินดาถาวร อ. “Elderly School and Quality of Life Development in Phiboonmangsaharn Municipality, Ubon Ratchathani Province”. Journal of Graduate School, Pitchayatat, Ubon Ratchathani Rajabhat University, vol. 14, no. 1, Apr. 2019, pp. 195-07, https://so02.tci-thaijo.org/index.php/Pitchayatat/article/view/221619.