Lertprapai, S. and Tiensuwan, M. (2015) “An application of multiple criteria decision making in combining environmental indices of five air pollution indicators”, Thailand Statistician, 7(2), pp. 131–145. available at: https://ph02.tci-thaijo.org/index.php/thaistat/article/view/34302 (accessed: 14 September 2026).