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  year = "1985"
}

@inproceedings{ bgf:Lixto,
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  publisher = "Morgan Kaufmann",
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  month = "September",
  year = "2001"
}

@article{ brachman-schmolze:kl-one,
  author = "Ronald~J. Brachman and James~G. Schmolze",
  title = "An overview of the {KL-ONE} knowledge representation system",
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  number = "2",
  pages = "171--216",
  month = "April--June",
  year = "1985"
}

@article{ gottlob:nonmon,
  author = "Georg Gottlob",
  title = "Complexity results for nonmonotonic logics",
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  number = "3",
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  year = "1992"
}

@article{ gls:hypertrees,
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}

@article{ levesque:functional-foundations,
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  title = "Foundations of a functional approach to knowledge representation",
  journal = "Artificial Intelligence",
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  number = "2",
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  month = "July",
  year = "1984"
}

@inproceedings{ levesque:belief,
  author = "Hector~J. Levesque",
  title = "A logic of implicit and explicit belief",
  booktitle = "Proceedings of the Fourth National Conference on Artificial Intelligence",
  publisher = "American Association for Artificial Intelligence",
  pages = "198--202",
  address = "Austin, Texas",
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  year = "1984"
}

@article{ nebel:jair-2000,
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  journal = "Journal of Artificial Intelligence Research",
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  pages = "271--315",
  year = "2000"
}