Boonnuch, W., V. Chinswangwatanakul, A. Methasate, T. Akaraviputh, V. Lohsiriwat, and D. Lohsiriwat. “Does Preoperative Chemoradiation Therapy in Locally Advanced Rectal Cancer Increase Rate of Sphincter Preserving Surgery? A Prospective Clinical Trial”. Siriraj Medical Journal, vol. 58, no. 4, Apr. 2006, pp. 743-6, https://he02.tci-thaijo.org/index.php/sirirajmedj/article/view/245754.