@inproceedings{DBLP:conf/ijcai/GuesgenJV87,
  author    = {Hans W. Guesgen and
               Ulrich Junker and
               Angi Vo{\ss}},
  title     = {Constraints in a Hybrid Knowledge Representation System},
  booktitle = {IJCAI},
  year      = {1987},
  pages     = {30-33},
  crossref  = {DBLP:conf/ijcai/1987},
  bibsource = {DBLP, http://dblp.uni-trier.de}
}

@proceedings{DBLP:conf/ijcai/1987,
  editor    = {John P. McDermott},
  title     = {Proceedings of the 10th International Joint Conference on
               Artificial Intelligence. Milan, Italy, August 1987},
  booktitle = {IJCAI},
  publisher = {Morgan Kaufmann},
  year      = {1987},
  bibsource = {DBLP, http://dblp.uni-trier.de}
}