- Proceedings of the 26th Annual International ACM SIGIR Conference on Research and Development in Information Retrieval, page 449-450. Toronto, Canada, ACM Press, (July 2003)
- Morgan Kaufmann, Amsterdam, (2003)
- American Documentation (1963)
- ACM Transactions on Knowledge Discovery from Data 2(2):1--25 (July 2008)
- Journal of Informetrics 3(1):49 - 63 (2009)


user