The US Coal Industry in the Nineteenth Century
Woodworth, J. "The History and Conditions of Mining in the Richmond Coal-Basin, Virginia." Transactions of the American Institute of Mining Engineers 31 (1902): 477-484. Yearley, Clifton Enterprise and Anthracite: Economics and Democracy in Schuylkill County, 1820-1875. Baltimore: The Johns Hopkins University Press, 1961.