1. Salton, G., Wong, A., Yang, C.S.: A vector space model for automatic indexing. Commun. ACM 18(11), 613–620 (1975)
2. Robertson, S.E., Walker, S., Jones, S., Hancock-Beaulieu, M., Gatford, M.: Okapi at trec-3. In: Proc. of TREC-3, Gaithersburg, Maryland, USA (1994)
3. Gao, G., Nie, J.Y., Bai, J.: Integrating word relationships into language models. In: SIGIR 2005: Proc. of the 28th int. conf. on Research and development in information retrieval, pp. 298–305. ACM Press, New York (2005)
4. Kleinberg, J.M.: Authoritative sources in a hyperlinked environment. J. ACM 46(5), 604–632 (1999)
5. Brin, S., Page, L.: The anatomy of a large-scale hypertextual web search engine. In: WWW7: Proc. of the 7th int. conf. on World Wide Web, pp. 107–117. Elsevier, Amsterdam (1998)