G. Mishne, and M. de Rijke. Proceedings ot the 7th International Conference on Computer-Assisted Information Retrieval (Recherche d'Information et ses Applications) - RIAO 2004, page 539--554. CID, (April 2004)
E. Voorhees. Proceedings of the 16th annual international ACM SIGIR conference on Research and development in information retrieval, page 171--180. New York, NY, USA, ACM, (1993)
M. Sanderson. Proceedings of the 17th annual international ACM SIGIR conference on Research and development in information retrieval, page 142--151. New York, NY, USA, Springer-Verlag New York, Inc., (1994)
H. Schütze, and J. Pedersen. Proceedings of the 4th Annual Symposium on Document Analysis and Information Retrieval, page 161--175. Las Vegas, USA, (1995)