M. Nurminen, и A. Heimbürger. Information Modelling and Knowledge Bases XXIII, том 237 из Frontiers in Artificial Intelligence and Applications, стр. 90-109. IOS Press, (2012)
M. Nurminen, и A. Heimbürger. Proceedings of the 21st European - Japanese Conference on Information Modelling and Knowledge Bases (EJC2011), vol. 1, стр. 97-116. Tallinn University of Technology, (2011)
J. Schmidt, H. Sehring, M. Skusa, и A. Wienberg. Proceedings of the Fifth East-European Conference on Advances in Databases and Information Systems, том 2151 из Lecture Notes in Computer Science, Springer, (2001)