1. Agrawal R. and Gehani N.H., “Rationale for the Design of Persistence and Query Processing Facilities in the Database Programming Language O++”, 2nd Int. Workshop on Database Programming Languages, Portland, OR, June 1989
2. Chakravarthy S., Blaustein B., Buchmann A. et al, “HiPAC: A Research Project in Active, Time-Constrained Database Management”, Final Technical Report, Xerox Advanced Information Technology Division. July 1989
3. Dayal U., “Active Database Management Systems”, Sigmod Record, Vol. 18, No. 3, 1989
4. Diaz O. and Paton N.W., “Sharing behaviour in an object-oriented database using a rule-based mechanism”, Proc. 9th British National Conference On Databases, 1991
5. Diaz O., Paton N. and Gray P., “A Rule Management in Object Oriented Databases: A Uniform Approach”, Proc. of the 17th Int. Conf. on Very Large Data Bases, Barcelona, Spain 1991