Schopenhauer, A. On the Fourfold Root of the Principle of Sufficient Reason, and On the Will in Nature: Two Essays (revised edition).
Chicago-viite (17. p.)Schopenhauer, Arthur. On the Fourfold Root of the Principle of Sufficient Reason, and On the Will in Nature: Two Essays (revised Edition).
MLA-viite (9. p.)Schopenhauer, Arthur. On the Fourfold Root of the Principle of Sufficient Reason, and On the Will in Nature: Two Essays (revised Edition).
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