1. SEQUEL 2: A unified approach to data definition, manipulation, and control;Chamberlin;IBM Journal of Research and Development,1976
2. A study of three database query languages;Greenblatt,1978
3. Computer programs for detecting and correcting spelling errors;Peterson;Communications of the ACM,1980
4. Use of psychological experimentation as an aid to development of a query language;Reisner;IEEE Transactions on Software and Engineering,1977
5. Another spelling correction program;Robinson;Communications of the ACM,1981