Koestler,Arthur. (1979). The sleepwalkers: A history of man's changing vision of the universe. Penguin Books.
शिकागो शैली (17वां संस्करण) प्रशस्ति पत्रKoestler,Arthur. The Sleepwalkers: A History of Man's Changing Vision of the Universe. Penguin Books, 1979.
एमएलए (9वां संस्करण) प्रशस्ति पत्रKoestler,Arthur. The Sleepwalkers: A History of Man's Changing Vision of the Universe. Penguin Books, 1979.
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