1. Gaizauskas, R., et al.: The university of sheffield’s trec 2003 q&a experiments. In: Proceedings of the 12th Text REtrieval Conference (2003)
2. Lecture Notes in Artificial Intelligence;P. Rosso,2005
3. Brill, E., et al.: Data-intensive question answering. In: Proceedings of the Tenth Text REtrieval Conference (TREC 2001), Gaithersburg, Maryland, November 2001, pp. 443–462 (2001)
4. Kong, K., et al.: Passage-based retrieval using parameterized fuzzy set operators. In: ACM SIGIR Workshop on Mathematical/Formal. Methods for Information Retrieval (2004)
5. Christensen, H.U.: Exploring the use of fuzzy logic and data fusion techniques in passage retrieval for QA. Master’s thesis, Aalborg University Esbjerg (December 2006)