Okapi at TREC-3: Automatic Query Construction and Other Experiments, Stephen E. Robertson, Stephen Walker, Michael Hancock, Ann Beaulieu, Mike Gatford, 1994Proceedings of the Third Text REtrieval Conference (TREC 3) (National Institute of Standards and Technology (NIST)) - 本文正式介绍了BM25排序函数,这是一种广泛用于基于关键词的信息检索算法。
Introduction to Information Retrieval, Christopher D. Manning, Prabhakar Raghavan, Hinrich Schütze, 2008 (Cambridge University Press) - 一本信息检索基础教科书,内容涵盖BM25等关键词模型以及结合搜索结果的策略。