P. Brusilovsky, R. Farzan, and J. Ahn. JCDL '05: Proceedings of the 5th ACM/IEEE-CS joint conference on Digital libraries, page 9--18. New York, NY, USA, ACM, (2005)
M. Kellar, C. Watters, and K. Inkpen. CHI '07: Proceedings of the SIGCHI conference on Human factors in computing systems, page 377--386. New York, NY, USA, ACM, (2007)
F. Gasparetti, and A. Micarelli. IUI '07: Proceedings of the 12th international conference on Intelligent user interfaces, page 325--328. New York, NY, USA, ACM Press, (2007)
K. Sugiyama, K. Hatano, and M. Yoshikawa. Proceedings of the 13th international conference on World Wide Web, page 675--684. New York, NY, USA, ACM, (2004)
C. Ullrich, K. Borau, H. Luo, X. Tan, L. Shen, and R. Shen. WWW '08: Proceeding of the 17th international conference on World Wide Web, page 705--714. New York, NY, USA, ACM, (2008)