Asawarungsaengkul, K. and Nanthavanij, S. (2015) “Hybrid Procedure for Optimal Design of Public Announcement System for Adequate Audibility”, Science & Technology Asia, 13(1), pp. 66–74. available at: https://ph02.tci-thaijo.org/index.php/SciTechAsia/article/view/41456 (accessed: 27 August 2026).