Darwin, C. (1952). The Origin of species by means of natural selection: The Descent of man and selection in relation to sex. Encyclopaedia Britannica.
Cita Chicago Style (17a ed.)Darwin, Charles. The Origin of Species by Means of Natural Selection: The Descent of Man and Selection in Relation to Sex. Chicago [etc.]: Encyclopaedia Britannica, 1952.
Cita MLA (9a ed.)Darwin, Charles. The Origin of Species by Means of Natural Selection: The Descent of Man and Selection in Relation to Sex. Encyclopaedia Britannica, 1952.
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