Hiriote, S., Phunphiphat, C. and Kunphong, P. (2021) “Cluster Analysis of Retirement Mutual Funds ”, Thai Journal of Operations Research : TJOR, 9(1), pp. 67–78. available at: https://ph02.tci-thaijo.org/index.php/TJOR/article/view/243912 (accessed: 24 September 2026).