Clifford, T. (2009). Rourke's World of Science ENCYCLOPEDIA: Volume 7 - Astronomy & Space. Rourke Publishing.
Chicago Style (17th ed.) CitationClifford, Tim. Rourke's World of Science ENCYCLOPEDIA: Volume 7 - Astronomy & Space. Rourke Publishing, 2009.
MLA (8th ed.) CitationClifford, Tim. Rourke's World of Science ENCYCLOPEDIA: Volume 7 - Astronomy & Space. Rourke Publishing, 2009.
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