@article{journals/jcss/EiterG96,
  title = "The Complexity of Nested Counterfactuals and Iterated Knowledge Base Revisions",
  author = "Thomas Eiter and Georg Gottlob",
  year = "1996",
  journal = "J. Comput. Syst. Sci.",
  number = "3",
  pages = "497-512",
  volume = "53",
}