Anthony C. Klug. Equivalence of Relational Algebra and Relational Calculus Query Languages Having Aggregate Functions. Journal of the ACM, 29(3):699-717, 1982. [doi]
@article{Klug82:1,
title = {Equivalence of Relational Algebra and Relational Calculus Query Languages Having Aggregate Functions},
author = {Anthony C. Klug},
year = {1982},
tags = {relational algebra, C++, algebra, query language},
researchr = {https://researchr.org/publication/Klug82%3A1},
cites = {0},
citedby = {0},
journal = {Journal of the ACM},
volume = {29},
number = {3},
pages = {699-717},
}