Ratanavaraha D. “Fiber Optic Laryngoscopy for Head and Neck Cancer: Technique, Limitation and Applications”. Journal of The Department of Medical Services 45, no. 2 (September 1, 2020): 200–204. Accessed May 9, 2024. https://he02.tci-thaijo.org/index.php/JDMS/article/view/245634.