1. Manning C D, Raghavan P, Schütze H. Introduction to Information Retrieval. Cambridge: Cambridge University Press, 2008
2. Chen H, Karger D R. Less is more: probabilistic models for retrieving fewer relevant documents. In: Proceedings of the 29th Annual International ACM SIGIR Conference on Research and Development in Information Retrieval. 2006, 429–436
3. Carbonell J G, Goldstein J. The use of MMR, diversity-based reranking for reordering documents and producing summaries. In: Proceedings of the 21st Annual International ACM SIGIR Conference on Research and Development in Information Retrieval. 1998, 335–336
4. Zhai C, Cohen W W, Lafferty J D. Beyond independent relevance: Methods and evaluation metrics for subtopic retrieval. In: Proceedings of the 26th Annal International ACM SIGIR Conference on Research and Development in Information Retrieval. 2003, 10–17
5. Wang J, Zhu J. Portfolio theory of information retrieval. In: Proceedings of the 32nd International ACM SIGIR Conference on Research and Development in Information Retrieval. 2009, 115–122