Lua APA (7ú heag.)
Spearman, C. (1973). The nature of 'intelligence' and the principles of cognition. Arno.
Lua i Stíl Chicago (17ú heag.)
Spearman, Charles. The Nature of 'Intelligence' and the Principles of Cognition. New York: Arno, 1973.
Lua MLA (9ú heag.)
Spearman, Charles. The Nature of 'Intelligence' and the Principles of Cognition. Arno, 1973.
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