@inproceedings{LAHS03a,
  title = "Keys, Nominals, and Concrete Domains",
  author = "Carsten Lutz and Carlos Areces and Ian Horrocks and Ulrike Sattler",
  year = "2003",
  booktitle = "Proc.\ of the 18th Int.\ Joint Conf.\ on Artificial Intelligence (IJCAI~2003)",
  isbn = "0-92705-663-7",
  pages = "349-354",
  publisher = "Morgan Kaufmann, Los Altos",
  url = "download/2003/LAHS03a.pdf",
}