Sirijaroonwong, Umarat, and Wasana Silangam. 2018. “Noise-Induced Hearing Loss, Noise Level on Road, Knowledge and Behavior for Prevention of Loosing Hearing Ability of Traffic Policemen in Surin Municipality”. Journal of Health Science of Thailand 19 (5):834-44. https://thaidj.org/index.php/JHS/article/view/1517.