A. Leuski. CIKM '01: Proceedings of the tenth international conference on Information and knowledge management, Seite 33--40. New York, NY, USA, ACM, (2001)
X. Liu, und W. Croft. ECIR'08: Proceedings of the IR research, 30th European conference on Advances in information retrieval, Seite 454--462. Berlin, Heidelberg, Springer-Verlag, (2008)
M. Hearst, und J. Pedersen. SIGIR '96: Proceedings of the 19th annual international ACM SIGIR conference on Research and development in information retrieval, Seite 76--84. New York, NY, USA, ACM, (1996)