Christian, S. (1998). What makes the grand canyon grand?: The world's most awe-insping natural wonders. J. Wiley.
Trích dẫn kiểu ChicagoChristian, Spencer. What Makes the Grand Canyon Grand?: The World's Most Awe-insping Natural Wonders. J. Wiley, 1998.
MLA CitationChristian, Spencer. What Makes the Grand Canyon Grand?: The World's Most Awe-insping Natural Wonders. J. Wiley, 1998.
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