Le Page, W. and Hidders, Jan and Michiels, P. and Paredaens, J. and Vercammen, R. (2005) On the expressive power of node construction in xquery. In: Doan, A. and Neven, F. and McCann, R. and Bex, G.J. (eds.) Proceedings of the Eight International Workshop on the Web & Databases: WebDB 2005. Association for Computing Machinery, pp. 85-90.

Calì, Andrea and Lembo, D. and Rosati, R. (2003) On the decidability and complexity of query answering over inconsistent and incomplete databases. In: Neven, F. and Beeri, C. and Milo, T. (eds.) Proceedings of the 22nd Symposium on Principles of Database Systems. ACM, pp. 260-271.