Day, R. A., & Underwood, A. L. (1991). Quantitative analysis (6th ed.). Prentice Hall.
Chicago Style aipamenaDay, R. A., and A. L. Underwood. Quantitative Analysis. 6th ed. Englewood Cliffs, NJ: Prentice Hall, 1991.
MLA aipamenaDay, R. A., and A. L. Underwood. Quantitative Analysis. 6th ed. Prentice Hall, 1991.
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