กฤษฎารักษ์ ฐปกรณ์, and หงส์วริทธิ์ธร ณัฐธนนท์. “The Effects of Partial Occlusion in Image-Based CAPTCHAs on Pass Rates”. JOURNAL OF INFORMATION SCIENCE AND TECHNOLOGY 3, no. 1 (June 30, 2012): 23–32. Accessed March 28, 2024. https://ph02.tci-thaijo.org/index.php/JIST/article/view/135207.