O'Brien, J. A. (1994). Introduction to information systems (7th ed.). Irwin.
Chicago-čujuhus (17. p.)O'Brien, James A. Introduction to Information Systems. 7th ed. Burr Ridge, Ill.: Irwin, 1994.
MLA-čujuhus (9. p.)O'Brien, James A. Introduction to Information Systems. 7th ed. Irwin, 1994.
Muitte dárkkistit čujuhemiid riektatvuođa, ovdal go geavahat daid iežat deavsttas.