Ippel, M. J. (1986). Component-testing: A theory of cognitive aptitude measurement. Free University Press.
Lua i Stíl Chicago (17ú heag.)Ippel, Martinus Johannes. Component-testing: A Theory of Cognitive Aptitude Measurement. Amsterdam: Free University Press, 1986.
Lua MLA (8ú heag.)Ippel, Martinus Johannes. Component-testing: A Theory of Cognitive Aptitude Measurement. Free University Press, 1986.
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