@article{DBLP:journals/cacm/SmithS77, author = {John Miles Smith and Diane C. P. Smith}, title = {Database Abstractions: Aggregation}, journal = {Commun. ACM}, volume = {20}, number = {6}, year = {1977}, pages = {405-413}, ee = {db/journals/cacm/SmithS77.html}, bibsource = {DBLP, http://dblp.uni-trier.de} }
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