Kristján Kristjánsson. (2013). Virtues and Vices in Positive Psychology (1.). Cambridge University Press.
Chicago Style aipamenaKristján Kristjánsson. Virtues and Vices in Positive Psychology. 1. Cambridge University Press, 2013.
MLA aipamenaKristján Kristjánsson. Virtues and Vices in Positive Psychology. 1. Cambridge University Press, 2013.
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