M. Atzmueller, and F. Lemmerich. International Symposium on Methodologies for Intelligent Systems (ISMIS), page 35--44. Berlin, Heidelberg, Springer Berlin Heidelberg, (2009)
H. Grosskreutz, S. Rüping, and S. Wrobel. European Conference on Machine Learning and Knowledge Discovery in Databases, page 440--456. Springer, (2008)