1. Bergman, M. and Kanoui, H. [1973] Application of Mechanical Theorem Proving to Symbolic Calculus, Third International Symposium on Advanced Computing Methods in Theoretical Physics, C.N.R.S., Marseille, June 1973.
2. Chang, C. L., [1976] DEDUCE: A Deductive Query Language for Relational Data Bases, In Pattern Recognition and Artificial Intelligence (C. H. Chen, Ed.), Academic Press, Inc., New York, 1976, 108–134.
3. Clark, K. L., Tarnlund, S. A. [1977] A First Order Theory of Data and Programs, Proceedings IFIP 77, North-Holland, 1977, 939–944.
4. Clark, K. L. [1978] Negation as Failure, In Logic and Data Bases (H. Gallaire and J. Minker, Eds.), Plenum Press, New York, 1978, 293–322.
5. Codd, E. F. [1970] A Relational Model for Large Shared Data Bases, CACM 13, 6 (June 1970), 377–387.