Protection through multimedia CAPTCHAs. - Wesam Al-Sudani; Amit Gill; Chen Li 016; Jidong Wang; Fei Liu 003 (MoMM, 2010)

Protection through Intelligent and Multimedia Captchas. - Wesam Al-Sudani; Amit Gill; Chen Li 016; Jidong Wang; Fei Liu 003 (Int. J. Adapt. Resilient Auton. Syst., 2012)