Keppel, G. (1991). Design and analysis: A researcher's handbook (3rd ed.). Prentice-Hall.
Cita Chicago (17th ed.)Keppel, Geoffrey. Design and Analysis: A Researcher's Handbook. 3rd ed. Englewood Cliffs, N.J: Prentice-Hall, 1991.
Cita MLA (9th ed.)Keppel, Geoffrey. Design and Analysis: A Researcher's Handbook. 3rd ed. Prentice-Hall, 1991.
Atenció: Aquestes cites poden no estar 100% correctes.