Stanford encyclopedia of philosophy: The Metaphysics Research Lab, Center for the Study of Language and Information, Stanford University. The Metaphysics Research Lab, Stanford Univ.
Chicago-viite (17. p.)Stanford Encyclopedia of Philosophy: The Metaphysics Research Lab, Center for the Study of Language and Information, Stanford University. Stanford, Calif.: The Metaphysics Research Lab, Stanford Univ.
MLA-viite (8. p.)Stanford Encyclopedia of Philosophy: The Metaphysics Research Lab, Center for the Study of Language and Information, Stanford University. The Metaphysics Research Lab, Stanford Univ.
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