A Generalized Constraint and Exception handler for an Object-Oriented CAD-DBMS. - Alejandro P. Buchmann; R. S. Carrera; M. A. Vazquez-Galindo (OODBS, 1986)

Handling Constraints and their Exceptions: An Attached Constraint Handler for Object-Oriented CAD Databases. - Alejandro P. Buchmann; R. S. Carrera; M. A. Vazquez-Galindo (On Object-Oriented Database System, 1991)