1. Andersen, W., Menzel, C.: Modal Rigidity in the OntoClean Methodology. In: Vieu, L., Varzi, A. (eds.) Formal Ontology and Information Systems: Collected Papers from the Fifth International Conference, pp. 119–127. IOS Press, Amsterdam (2004)
2. Artale, A., Franconi, E., Guarino, N., Pazzi, L.: Part-Whole Relations in Object-Centered Systems: an Overview. Data & Knowledge Engineering 20(3), 347–383 (1996)
3. Boella, G., van der Torre, L., Verhagen, H.: Roles, an Interdisciplinary Perspective. Applied Ontology 2(2), 81–88 (2007)
4. Brachman, R.J.: On the Epistemological Status of Semantic Networks. In: Findler, N.V. (ed.) Associative Networks: Representation and Use of Knowledge by Computers. Academic Press, London (1979)
5. Brachman, R., Fikes, R., Levesque, H.: Krypton: A Functional Approach to Knowledge Representation. IEEE Computer 116(10), 67–73 (1983)