@Proceedings{dau05contributions,

  title  = {Contributions to ICCS 2005},

  year   = {2005},
  number = {},
  url    = {http://www.kde.cs.uni-kassel.de/conf/iccs05},

  const  = {\ text}
}
@Proceedings{conf/iccs/2005,

  title  = {Conceptual Structures: Common Semantics for Sharing Knowledge, 13th International Conference on Conceptual Structures, ICCS 2005, Kassel, Germany, July 17-22, 2005, Proceedings},

  year   = {2005},
  number = {},
  url    = {http://www.kde.cs.uni-kassel.de/conf/iccs05},

  const  = {\ text}
}
@Proceedings{stumme00working,

  title  = {Working with Conceptual Structures -- Contributions to ICCS 2000. Suppl. Proc. 8th International
                  Conference on Conceptual Structures (ICCS 2000)},

  year   = {2000},
  number = {},
  url    = {},

  const  = {\ text}
}