E. Liarou, S. Idreos, and M. Koubarakis. Proceedings of the 6th International Semantic Web Conference and 2nd Asian Semantic Web Conference (ISWC/ASWC2007), Busan, South Korea, volume 4825 of LNCS, page 323--336. Berlin, Heidelberg, Springer Verlag, (November 2007)
I. Zaihrayeu, L. Sun, F. Giunchiglia, W. Pan, Q. Ju, M. Chi, and X. Huang. Proceedings of the 6th International Semantic Web Conference and 2nd Asian Semantic Web Conference (ISWC/ASWC2007), Busan, South Korea, volume 4825 of LNCS, page 617--630. Berlin, Heidelberg, Springer Verlag, (November 2007)