1. The long tail: Why the future of business is selling more of less;Anderson,2006
2. Baeza-Yates, R., Caldeŕon-Benavides, L., & Gonźalez, C. (2006). In The intention behind Web queries (pp. 98–109). Paper presented at the string processing and information retrieval (SPIRE 2006), 11–13 October, Glasgow, Scotland.
3. Automatic classification of Web queries using very large unlabeled query logs;Beitzel;ACM Transactions on Information Systems,2007
4. Anomalous states of knowledge as a basis for information retrieval;Belkin;Canadian Journal of Information Science,1980
5. Belkin, N. J. (1993). Interaction with texts: Information retrieval as information-seeking behavior. In Information retrieval ’93, Von der Modellierung zur Anwendung (pp. 55–66). Konstanz, Germany: Universitaetsverlag Konstanz.