Ullman, J. D. (1982). Principles of Database Systems (2nd ed.). Computer Science Press.
Chicago-viite (17. p.)Ullman, Jeffrey D. Principles of Database Systems. 2nd ed. 11 Taft Court, Rockville, Maryland 20850: Computer Science Press, 1982.
MLA-viite (9. p.)Ullman, Jeffrey D. Principles of Database Systems. 2nd ed. Computer Science Press, 1982.
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