@INCOLLECTION{AmatoL01,
  author = {Gianluca Amato and James Lipton},
  title = {Indexed Categories and Bottom-Up Semantics of Logic Programs},
  booktitle = {Logic for Programming, Artificial Intelligence, and Reasoning, 8th
        International Conference, LPAR 2001 Havana, Cuba, December 3--7,
        2001 Proceedings},
  publisher = {Springer},
  year = {2001},
  editor = {Robert Nieuwenhuis and Andrei Voronkov},
  volume = {2250},
  series = {Lecture Notes in Artificial Intelligence},
  pages = {438--454},
  doi = {10.1007/3-540-45653-8{\_}30},
  isbn = {978-3-540-42957-9}
}