Alf Zugenmaier. Countering Automated Exploits with System Security CAPTCHAS. In Bruce Christianson, Bruno Crispo, James A. Malcolm, Michael Roe, editors, Security Protocols, 13th International Workshop, Cambridge, UK, April 20-22, 2005, Revised Selected Papers. Volume 4631 of Lecture Notes in Computer Science, pages 170-179, Springer, 2005. [doi]
Abstract is missing.