Gaarder, J., & Moller, P. (1995). Sophie's world: A novel about the history of philosophy. Phoenix House.
Chicago-viite (17. p.)Gaarder, Jostein, ja Paulette Moller. Sophie's World: A Novel About the History of Philosophy. London: Phoenix House, 1995.
MLA-viite (9. p.)Gaarder, Jostein, ja Paulette Moller. Sophie's World: A Novel About the History of Philosophy. Phoenix House, 1995.
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