APA (7th ed.) Zitazioa
Nettle, D. (2005). Happiness: The science behind your smile. Oxford University Press.
Chicago Style (17th ed.) Zitazioa
Nettle, Daniel. Happiness: The Science Behind Your Smile. Oxford, UK ; New York, N.Y.: Oxford University Press, 2005.
MLA (9th ed.) Zitazioa
Nettle, Daniel. Happiness: The Science Behind Your Smile. Oxford University Press, 2005.
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