Gray, J. E. (2003). Geologic Studies of mercury by the U.S. Geological Survey. US Geological Survey circular 1248.
Chicago Style aipamenaGray, John E. "Geologic Studies of Mercury By the U.S. Geological Survey." US Geological Survey Circular 1248 2003.
MLA aipamenaGray, John E. "Geologic Studies of Mercury By the U.S. Geological Survey." US Geological Survey Circular 1248 2003.
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