Skurzynski, G. (2004). Are we alone?: Scientists search for life in space. National Geographic Society.
शिकागो शैली (17वां संस्करण) प्रशस्ति पत्रSkurzynski, Gloria. Are We Alone?: Scientists Search for Life in Space. Washington, DC: National Geographic Society, 2004.
एमएलए (8वां संस्करण) प्रशस्ति पत्रSkurzynski, Gloria. Are We Alone?: Scientists Search for Life in Space. National Geographic Society, 2004.
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