ชาติรังสรรค์ มณีรัตน์, and ตั้งมณี ชัชพงศ์. “Effects of Typefaces, Rotations and Sets of Characters of Text-Based CAPTCHA on Human Affirmative Rates”. JOURNAL OF INFORMATION SCIENCE AND TECHNOLOGY 4, no. 2 (December 30, 2013): 16–23. Accessed May 26, 2024. https://ph02.tci-thaijo.org/index.php/JIST/article/view/135363.