1. On the power of languages for the manipulation of complex objects;Abiteboul,1988
2. Space usage in functional query languages;Abiteboul,1995
3. Fixpoint extensions of first-order logic and Datalog-like languages;Abiteboul,1989
4. University of data retrieval languages;Aho,1979
5. A powerful and simple database language;Bancilhon,1988