Pablo Barceló, Leonid Libkin, Antonella Poggi, Cristina Sirangelo. XML with incomplete information: models, properties, and query answering. In Jan Paredaens, Jianwen Su, editors, Proceedings of the Twenty-Eigth ACM SIGMOD-SIGACT-SIGART Symposium on Principles of Database Systems, PODS 2009, June 19 - July 1, 2009, Providence, Rhode Island, USA. pages 237-246, ACM, 2009. [doi]
Abstract is missing.