@InProceedings{thielscher:KI99,
  author = 	"Michael Thielscher",
  title = 	"A Theory of First-Order Counterfactual Reasoning",
  booktitle = 	"Proceedings of the German Annual Conference on
		  Artificial Intelligence (KI)",
  year = 	"1999",
  editor =	"T.\ Christaller",
  pages =	"137--148",
  volume =      "1701",
  series =      "LNAI",
  publisher =	"Springer",
  address =	"Bonn, Germany",
  month =	sep
}