Gaarder, J. 1. (1996). Sophie's world: A novel about the history of philosophy. Berkley Books.
Chicago-viite (17. p.)Gaarder, Jostein 1952. Sophie's World: A Novel About the History of Philosophy. New York: Berkley Books, 1996.
MLA-viite (9. p.)Gaarder, Jostein 1952. Sophie's World: A Novel About the History of Philosophy. Berkley Books, 1996.
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