[IR] 相關資料與API

[API]
Lucene http://lucene.apache.org/java/2_4_1/api/index.html
BM25 http://nlp.uned.es/~jperezi/Lucene-BM25/javadoc/

[資料]
WordNet for Java http://lyle.smu.edu/~tspell/jaws/index.html#get_started
Lucene電子書 http://www.cnblogs.com/lhdyesok/archive/2006/10/05/521865.html
Lucene各種檢索介紹 http://blog.csdn.net/juicewall/archive/2008/11/21/3347338.aspx