1. Agarwal, R., Gehani, N.: Ode (Object database and environment): The language and the data model. In: Proceedings of the ACM-SIGMOD International Conference on Management of Data, Portland, OR, pp. 36–45 (May 1989)
2. Berson, T.A., Lunt, T.F.: Multilevel Security for Knowledge-Based Systems. In: Proceedings of the IEEE Symposium on Research in Security and Privacy, Oakland, CA, pp. 235–242 (April 1987)
3. Boulahia-Cuppens, N., Cuppens, F., Gabillon, A., Yazdanian, K.: Virtual View Model to Design a Secure Object-Oriented Database. In: Proceedings of the National Computer Security Conference, Baltimore, MD, pp. 66–76 (October 1994)
4. Buchman, A.P., Branding, H., Kundrass, T., Zimmermann, J.: REACH: A REal-time ACtive and Heterogeneous Mediator System. Bulletin of the IEEE Technical Committee on Data Engineering 15(4) (December 1992)
5. Ceri, S., Manthey, R.: Consolidated specification of Chimera, the conceptual interface of idea. Technical Report IDEA.DD.2P.004, Politecnico di Milano, Milan, Italy (June 1993)