E. Chi, and T. Mytkowicz. HT '08: Proceedings of the nineteenth ACM conference on Hypertext and hypermedia, page 81--88. New York, NY, USA, ACM, (2008)
A. Hotho, R. Jäschke, C. Schmitz, and G. Stumme. The Semantic Web: Research and Applications, volume 4011 of Lecture Notes in Computer Science, page 411--426. Berlin/Heidelberg, Springer, (June 2006)
A. Takasu. JCDL '03: Proceedings of the 3rd ACM/IEEE-CS joint conference on Digital libraries, page 49--60. Washington, DC, USA, IEEE Computer Society, (2003)