Crooks, R. L. (1991). Psychology: Science, behavior, and life (2nd ed.). Holt, Rinehart and Winston.
Lua i Stíl Chicago (17ú heag.)Crooks, Robert L. Psychology: Science, Behavior, and Life. 2nd ed. Chicago: Holt, Rinehart and Winston, 1991.
Lua MLA (9ú heag.)Crooks, Robert L. Psychology: Science, Behavior, and Life. 2nd ed. Holt, Rinehart and Winston, 1991.
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