Não informado. (1961). Satellite situation report. National Aeronautics and Space Administration, Goddard Space Flight Center.
शिकागो शैली (17वां संस्करण) प्रशस्ति पत्रNão informado. Satellite Situation Report. Greenbelt, Md: National Aeronautics and Space Administration, Goddard Space Flight Center, 1961.
एमएलए (8वां संस्करण) प्रशस्ति पत्रNão informado. Satellite Situation Report. National Aeronautics and Space Administration, Goddard Space Flight Center, 1961.
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