The following publications are possibly variants of this publication:
- Tractable Query Answering over Conceptual Schemata (Extended Abstract)Andrea Calì, Georg Gottlob, Andreas Pieris. sebd 2010: 454-461
- Datalog Extensions for Tractable Query Answering over OntologiesAndrea Calì, Georg Gottlob, Thomas Lukasiewicz. In Roberto De Virgilio, Fausto Giunchiglia, Letizia Tanca, editors, Semantic Web Information Management - A Model-Based Perspective. pages 249-279, Springer, 2009. [doi]
- Tractable Query Answering over Ontologies with Datalog+/-Andrea Calì, Georg Gottlob, Thomas Lukasiewicz. dlog 2009: [doi]
- A general datalog-based framework for tractable query answering over ontologiesAndrea Calì, Georg Gottlob, Thomas Lukasiewicz. PODS 2009: 77-86 [doi]
- A general Datalog-based framework for tractable query answering over ontologiesAndrea Calì, Georg Gottlob, Thomas Lukasiewicz. ws, 14:57-83, 2012. [doi]