Martin Grohe, Julian Mariño. Definability and Descriptive Complexity on Databases of Bounded Tree-Width. In Catriel Beeri, Peter Buneman, editors, Database Theory - ICDT 99, 7th International Conference, Jerusalem, Israel, January 10-12, 1999, Proceedings. Volume 1540 of Lecture Notes in Computer Science, pages 70-82, Springer, 1999. [doi]
Abstract is missing.