Wittgenstein, L. (1958). Preliminary studies for the "philosophical investigations": The blue and brown books. Harper.
Chicago-čujuhus (17. p.)Wittgenstein, Ludwig. Preliminary Studies for the "Philosophical Investigations": The Blue and Brown Books. New York: Harper, 1958.
MLA-čujuhus (9. p.)Wittgenstein, Ludwig. Preliminary Studies for the "Philosophical Investigations": The Blue and Brown Books. Harper, 1958.
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