Boonnithi, N., and P. Santichatngam. “The Severity of Pain during Hemorrhoidectomy under Local Anesthesia in Maharat Nakhon Ratchasima Hospital”. Maharat Nakhon Ratchasima Hospital Journal, vol. 25, no. 3, Oct. 2024, pp. 151-6, https://he04.tci-thaijo.org/index.php/MNRHJ/article/view/2207.