1. Lieberman, H.: Letizia: An Agent That Assists Web Browsing. IJCAI (1995)
2. Joachims, T., Freitag, D., Mitchell, T.: WebWatcher: A Tour Guide for the World Wide Web. In: IJCAI 1997 (1997)
3. Chen, L., Sycara, K.: WebMate: A Personal Agent for Browsing and Searching. In: Proc. 2nd Intl. Conf. on Auton. Agents and Multi Agent Sys., AGENTS 1998 (1998)
4. Lecture Notes in Computer Science;M. Jaczynski,1998
5. Mladenic, D.: Machine learning used by Personal WebWatcher. In: Proc. of ACAI 1999 Workshop on Machine Learning and Intelligent Agents (1999)