@article{journals/iandc/GottlobP03,
  title = "On the complexity of single-rule datalog queries",
  author = "Georg Gottlob and Christos H. Papadimitriou",
  year = "2003",
  journal = "Inf. Comput.",
  number = "1",
  pages = "104-122",
  volume = "183",
  doi = "10.1016/S0890-5401(03)00012-9",
}