Wittgenstein, L. (1958). Preliminary studies for the "philosophical investigations": The blue and brown books. Harper.
शिकागो शैली (17वां संस्करण) प्रशस्ति पत्रWittgenstein, Ludwig. Preliminary Studies for the "Philosophical Investigations": The Blue and Brown Books. New York: Harper, 1958.
एमएलए (9वां संस्करण) प्रशस्ति पत्रWittgenstein, Ludwig. Preliminary Studies for the "Philosophical Investigations": The Blue and Brown Books. Harper, 1958.
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