ผลประเสริฐ พ. and วิทยถาวรวงศ์ พ. (2018) “The Effectiveness of the Process of Developing the Life Quality of the Elderly under the Sufficiency Economy: A Case Study Lom Kao District, Phetchabun Province”, Journal of Preventive Medicine Association of Thailand, 6(3), pp. 240–255. Available at: https://he01.tci-thaijo.org/index.php/JPMAT/article/view/132938 (Accessed: 7 May 2024).