Hannan, B. (2009). The riddle of the world: A reconsideration of Schopenhauer's philosophy. Oxford University Press.
Čikaški stil citiranja (17. izdanje)Hannan, Barbara. The Riddle of the World: A Reconsideration of Schopenhauer's Philosophy. Oxford ; New York: Oxford University Press, 2009.
MLA način citiranja (9. izdanje)Hannan, Barbara. The Riddle of the World: A Reconsideration of Schopenhauer's Philosophy. Oxford University Press, 2009.
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