@article{journals/corr/cs-AI-0207072, title = "Complexity of Nested Circumscription and Nested Abnormality Theories", author = "Marco Cadoli and Thomas Eiter and Georg Gottlob", year = "2002", journal = "{CoRR}", url = "http://arxiv.org/abs/cs.AI/0207072", volume = "cs.AI/0207072", }