Wall, J. S. (1884). Report on the coal mines of the Monongahela River Region, from the West-Virginia state line to Pittsburgh, including the mines on the lower Youghiogheny River. Board of Commissioners for the Second Geological Survey of Pennsylvania.
Chicago-Zitierstil (17. Ausg.)Wall, J. Sutton. Report on the Coal Mines of the Monongahela River Region, from the West-Virginia State Line to Pittsburgh, Including the Mines on the Lower Youghiogheny River. Harrisburg: Board of Commissioners for the Second Geological Survey of Pennsylvania, 1884.
MLA-Zitierstil (9. Ausg.)Wall, J. Sutton. Report on the Coal Mines of the Monongahela River Region, from the West-Virginia State Line to Pittsburgh, Including the Mines on the Lower Youghiogheny River. Board of Commissioners for the Second Geological Survey of Pennsylvania, 1884.