C. Ziegler, G. Lausen, and S. Lars. Proceedings of the thirteenth ACM international conference on Information and knowledge management, page 406--415. New York, NY, USA, ACM, (2004)
C. Ziegler, L. Schmidt-Thieme, and G. Lausen. Proc. of the 2nd ACM SIGIR Semantic Web and Information Retrieval Workshop (SWIR '04), Sheffield, UK, (2004)
J. Zhu, M. Ma, J. Guo, and Z. Wang. INTERNATIONAL JOURNAL OF PATTERN RECOGNITION AND ARTIFICIAL INTELLIGENCE, 21 (2):
375-395(March 2007)International Workshop on Web Personalization, Recommender Systems and
Intelligent User Interfaces, Reading, ENGLAND, OCT, 2005.