Francaviglia, R. V. (1991). Hard places: Reading the landscape of America's historic mining districts. University of Iowa Press.
Чикаго-гийн эшлэл (17 дахь хэвлэлт)Francaviglia, Richard V. Hard Places: Reading the Landscape of America's Historic Mining Districts. Iowa City, Iowa: University of Iowa Press, 1991.
MLA -ийн эшлэл (9 дэх хэвлэлт)Francaviglia, Richard V. Hard Places: Reading the Landscape of America's Historic Mining Districts. University of Iowa Press, 1991.
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