M. Atzmueller, S. Beer, and F. Puppe. Proc. 22nd International Florida Artificial Intelligence Research Society Conference (FLAIRS), page 402--407. AAAI Press, (2009)
M. Freiberg, and F. Puppe. Proceedings of the International Conference on Knowledge Engineering and Ontology Development (KEOD 2012), SciTePress Digital Library, (2012)