Interactive Support For Non-Programmers: The Relational and Network Approaches.

http://doi.acm.org/10.1145/800297.811529 db/conf/sigmod/CoddD74.html E. F. Codd C. J. Date Interactive Support For Non-Programmers: The Relational and Network Approaches. 11-41 SIGFIDET74-2/P011.pdf 1974 conf/sigmod/74 SIGMOD Workshop, Vol. 2 db/conf/sigmod/sigmod74-2.html#CoddD74