Não informado. (1961). Satellite situation report. National Aeronautics and Space Administration, Goddard Space Flight Center.
Παραπομπή σε μορφή Chicago (17η εκδ.)Não informado. Satellite Situation Report. Greenbelt, Md: National Aeronautics and Space Administration, Goddard Space Flight Center, 1961.
Παραπομπή σε μορφή MLA (8th εκδ.)Não informado. Satellite Situation Report. National Aeronautics and Space Administration, Goddard Space Flight Center, 1961.
Πρόσοχή: Οι παραπομπές μπορεί να μην είναι 100% ακριβείς.