@inproceedings{CalvaneseEtAl2008AggregateOntologies,
   title = "{Aggregate Queries over Ontologies}",
   year = "2008",
   author = "Diego Calvanese and Evgeny Kharlamov and Werner Nutt and Camilo Thorne",
   booktitle = "Proc.\ {CIKM}, {ONISW} workshop".
   address = {Napa Valley, USA}
}