Bo-Yeong Kang Dae-Won Kim Sang-Jo Lee Semantic Indexing and Fuzzy Relevance Model in Information Retrieval. 49-60 2005 Computational Intelligence for Modelling and Prediction http://dx.doi.org/10.1007/10966518_4 series/sci/2005-2 db/series/sci/sci2.html#KangKL05