1. & (2002). The use of unlabeled data to improve supervised learning for text summarization, In Proceedings of the 25th annual International ACM Conference on Research and Development in Information Retrieval (SIGIR'02) (pp. 105–112). New York: ACM Press.
2. Machine-Made Index for Technical Literature—An Experiment
3. (2006). Manhattan distance, in Dictionary of Algorithms and Data Structures, ed., Gaithersburg, MS: U.S. National Institute of Standards and Technology.
4. 31 May 2006. (Last accessed 17 January 2008) Available from: http://www.nist.gov/dads/HTML/manhattanDistance.html