Cohen, N. (1989). Gravity's lens: Views of the new cosmology. John Wiley and Sons.
शिकागो शैली (17वां संस्करण) प्रशस्ति पत्रCohen, Nathan. Gravity's Lens: Views of the New Cosmology. New York: John Wiley and Sons, 1989.
एमएलए (9वां संस्करण) प्रशस्ति पत्रCohen, Nathan. Gravity's Lens: Views of the New Cosmology. John Wiley and Sons, 1989.
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