1. 1Language and Computing, Maaltecenter Blok A 3, Derbystraat 79, B-9051 Sint-Denijs- Westrem, Belgium
2. 2Language and Computing, Maaltecenter Blok A 3, Derbystraat 79, B-9051 Sint-Denijs-Westrem, Belgium
3. 3Institute for Formal Ontology and Medical Information Science, University of Leipzig, Germany United States of America
4. 4Department of Philosophy, University at Buffalo, NY, United States of America