@InProceedings{Kent:1999:UML,
  author =       "Stuart Kent and John Howse",
  title =        "Mixing Visual and Textual Constraint Languages",
  pages =        "384--398",
  booktitle =    "UML'99 - The Unified Modeling Language. Beyond the
                  Standard. Second International Conference, Fort Collins,
                  CO, USA, October 28-30. 1999, Proceedings",
  editor =       "Robert France and Bernhard Rumpe",
  publisher =    "Springer",
  series =       "LNCS",
  volume =       "1723",
  year =         "1999",
}