B. Ganter, und C. Meschke. Rough Sets, Fuzzy Sets, Data Mining and Granular Computing, 12th International Conference, RSFDGrC 2009, Delhi, India, December 15-18, 2009. Proceedings, Volume 5908 von Lecture Notes in Computer Science, Seite 117-126. (2009)
Y. Yao, und J. Mi. RSKT '09: Proceedings of the 4th International Conference on Rough Sets and Knowledge Technology, Seite 601--609. Berlin, Heidelberg, Springer-Verlag, (2009)