Lewis, D. (1967). Statistical methods in education. University of London Press.
Cita Chicago (17th ed.)Lewis, D.G. Statistical Methods in Education. Lomdon: University of London Press, 1967.
Cita MLA (9th ed.)Lewis, D.G. Statistical Methods in Education. University of London Press, 1967.
Atenció: Aquestes cites poden no estar 100% correctes.