B. Krause, R. Jäschke, A. Hotho, and G. Stumme. HT '08: Proceedings of the Nineteenth ACM Conference on Hypertext and Hypermedia, page 157-166. New York, NY, USA, ACM, (2008)
M. Carman, M. Baillie, and F. Crestani. SSM '08: Proceeding of the 2008 ACM workshop on Search in social media, page 27--34. New York, NY, USA, ACM, (2008)