S. Ries, J. Kangasharju, and M. Mühlhäuser. On the Move to Meaningful Internet Systems 2006: OTM 2006 Workshops, volume 4277 of Lecture Notes in Computer Science, page 894--903. Berlin/Heidelberg, Springer, (2006)
A. Gangemi, A. Gliozzo, and V. Presutti. Proceedings of the 6th International Semantic Web Conference and 2nd Asian Semantic Web Conference (ISWC/ASWC2007), Busan, South Korea, volume 4825 of LNCS, page 757--770. Berlin, Heidelberg, Springer Verlag, (November 2007)