Shelton, W. (1967). American space exploration: The first decade. Boston: Little, Brown and Company.
Παραπομπή Chicago StyleShelton, William. American Space Exploration: The First Decade. Boston: Little, Brown and Company, 1967.
Παραπομπή MLAShelton, William. American Space Exploration: The First Decade. Boston: Little, Brown and Company, 1967.
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