Mariano P. Consens, Alberto O. Mendelzon. Low Complexity Aggregation in GraphLog and Datalog. In Serge Abiteboul, Paris C. Kanellakis, editors, ICDT 90, Third International Conference on Database Theory, Paris, France, December 12-14, 1990, Proceedings. Volume 470 of Lecture Notes in Computer Science, pages 379-394, Springer, 1990. [doi]
Abstract is missing.