Jan Paredaens, Dirk Van Gucht. Possibilities and Limitations of Using Flat Operators in Nested Algebra Expressions. In Proceedings of the Seventh ACM SIGACT-SIGMOD-SIGART Symposium on Principles of Database Systems, March 21-23, 1988, Austin, Texas. pages 29-38, ACM, 1988. [doi]
Abstract is missing.