Richards, R. J. Darwin on mind, morals and emotions: Robert J. Richards. The Cambridge Companion to Darwin.(2006).
Chicago-viite (17. p.)Richards, Robert J. "Darwin on Mind, Morals and Emotions: Robert J. Richards." The Cambridge Companion to Darwin.(2006) .
MLA-viite (8. p.)Richards, Robert J. "Darwin on Mind, Morals and Emotions: Robert J. Richards." The Cambridge Companion to Darwin.(2006), .
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