R. Jäschke, A. Hotho, F. Mitzlaff, and G. Stumme. Recommender Systems for the Social Web, volume 32 of Intelligent Systems Reference Library, Springer, Berlin/Heidelberg, (2012)
M. Grahl, A. Hotho, and G. Stumme. Workshop Proceedings of Lernen - Wissensentdeckung - Adaptivität (LWA 2007), page 50-54. Martin-Luther-Universität Halle-Wittenberg, (September 2007)
S. Bao, G. Xue, X. Wu, Y. Yu, B. Fei, and Z. Su. WWW '07: Proceedings of the 16th international conference on World Wide Web, New York, NY, USA, ACM Press, (2007)
B. Krause, A. Hotho, and G. Stumme. Advances in Information Retrieval, 30th European Conference on IR Research, ECIR 2008, 4956, page 101-113. Springer, (2008)
M. Noll, and C. Meinel. Proceedings of the 6th International Semantic Web Conference and 2nd Asian Semantic Web Conference (ISWC/ASWC2007), Busan, South Korea, volume 4825 of LNCS, page 365--378. Berlin, Heidelberg, Springer Verlag, (November 2007)