@InProceedings{HendersonSellers:1998:OPEU,
  author =       "Brian Henderson-Sellers",
  title =        "{OML}: Proposals to Enhance {UML}",
  pages =        "319--329",
  booktitle =    "The Unified Modeling Language, UML'98 - Beyond the
                  Notation. First International Workshop, Mulhouse, France,
                  June 1998",
  editor =       "Jean B{\'e}zivin and Pierre-Alain Muller",
  year =         "1998",
}