Keller, G., Bartel, H., & Warrack, B. (1990). Statistics for management and economics: A system approach (2nd ed.). Wadsworth.
Čikaški stil citiranja (17. izdanje)Keller, Gerald, Henry Bartel, i Brian Warrack. Statistics for Management and Economics: A System Approach. 2nd ed. Belmont, Calif: Wadsworth, 1990.
MLA način citiranja (9. izdanje)Keller, Gerald, et al. Statistics for Management and Economics: A System Approach. 2nd ed. Wadsworth, 1990.
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