Whangmahaporn, P., P. Simmonds, and B. Whangmahaporn. “Factors Affecting Quality of Life of the Elderly in Thailand”. Asian Political Science Review, vol. 2, no. 2, Jan. 2020, pp. 79-87, https://so01.tci-thaijo.org/index.php/APSR/article/view/234083.