A. I. Azrin and M. F. Abdul Ghafir, “Investigation of Different Emissions Tax Calculation Methods for Kuala Lumpur International Airport”, PAAT, vol. 4, no. 2, pp. 51–59, Dec. 2024, Accessed: Aug. 12, 2026. [Online]. Available: https://journal.uthm.edu.my/index.php/paat/article/view/16789