Logic System of Concept Graphs with Negation And Its Relationship to Predicate Logic Dau Frithjof Heftet / 2003 / Engelsk
Conceptual Structures: Common Semantics for Sharing Knowledge 13th International Conference on Conceptual Structures, ICCS 2005, Kassel, Germany, July 17-22, 2005, Proceedings Dau Frithjof Heftet / 2005 / Engelsk
Conceptual Structures: Leveraging Semantic Technologies 17th International Conference on Conceptual Structures, ICCS 2009, Moscow, Russia, July 26-31, 2009, Proceedings Rudolph Sebastian Heftet / 2009 / Engelsk