Keppel, G. (1991). Design and analysis: A researcher's handbook (3rd ed.). Prentice Hall.
Chicago Style aipamenaKeppel, Geoffrey. Design and Analysis: A Researcher's Handbook. 3rd ed. Englewood Cliffs, N.J: Prentice Hall, 1991.
MLA aipamenaKeppel, Geoffrey. Design and Analysis: A Researcher's Handbook. 3rd ed. Prentice Hall, 1991.
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