M. Hearst, и J. Pedersen. SIGIR '96: Proceedings of the 19th annual international ACM SIGIR conference on Research and development in information retrieval, стр. 76--84. New York, NY, USA, ACM, (1996)
U. Shardanand, и P. Maes. CHI '95: Proceedings of the SIGCHI conference on Human factors in computing systems, стр. 210--217. New York, NY, USA, ACM Press/Addison-Wesley Publishing Co., (1995)
W. Hill, L. Stead, M. Rosenstein, и G. Furnas. CHI '95: Proceedings of the SIGCHI conference on Human factors in computing systems, стр. 194--201. New York, NY, USA, ACM Press/Addison-Wesley Publishing Co., (1995)