Allman, Eric; Stonebraker, Michael; Held, Gerald "Embedding a relational data sublanguage in a general purpose programming language" pp25-35

[ACM SIGMOD/PODS] (1976) [ACM SIGMOD/PODS] Proceedings of the 1976 SIGMOD/PODS Conference on Data : Abstraction, definition and structure June 02-04, 1976, Washington, D.C.  

Languages mentioned EQUEL {1976}