Pansrinua, Weeraphol, Anurak Tripetch, and Piti Chantruthai. “A Study of Operating Speed Limits for Vehicles Driving on Ratchadamnoen Road Nakhon Si Thammarat”. Journal of Bansomdej Engineering and Industrial Technology 3, no. 2 (December 31, 2022): 79–92. accessed April 13, 2025. https://ph04.tci-thaijo.org/index.php/JEITB/article/view/4050.