Spadley, J. L. (1994). Visions that shaped the universe: A history of scientific ideas about the universe. McGraw-hill.
Chicago-viite (17. p.)Spadley, Joseph L. Visions That Shaped the Universe: A History of Scientific Ideas About the Universe. New York: McGraw-hill, 1994.
MLA-viite (9. p.)Spadley, Joseph L. Visions That Shaped the Universe: A History of Scientific Ideas About the Universe. McGraw-hill, 1994.
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