Porterfield, J. (2018). The benefits of spaceflight and space exploration (First edition.). Britannica Educational Publishing in association with Rosen Educational Services.
शिकागो शैली (17वां संस्करण) प्रशस्ति पत्रPorterfield, Jason. The Benefits of Spaceflight and Space Exploration. First edition. New York, NY: Britannica Educational Publishing in association with Rosen Educational Services, 2018.
एमएलए (8वां संस्करण) प्रशस्ति पत्रPorterfield, Jason. The Benefits of Spaceflight and Space Exploration. First edition. Britannica Educational Publishing in association with Rosen Educational Services, 2018.
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