Author
United States. Bureau of Mines
9
McCulloch, C. M.
4
Appalachian Regional Commission
2
Bushnell, Kent O.
2
Geological Survey (U.S.)
2
Geological Survey (U.S.),
2
Kertis, Carla A.
2
Lesser, William
2
Phalen, W. C. 1877-1949
2
United States. Department of the Interior. Southwestern Pennsylvania Heritage Preservation Commission
2
United States. National Park Service. Denver Service Center
2
Ash, S. H. 1889-
1
Ashmead, Dever C. 1884-
1
Barnes, Ivan, 1931-1989,
1
Bastin, Edson S. 1878-1953
1
Bench, B. M.
1
Briggs, Reginald P., 1929-2009
1
Buch, John Willard
1
Burgan, Michael
1
Chekan, G. J.
1
Conner, Eli T.
1
Darton, Nelson Horatio, 1865-1948
1
Davies, William E. 1917-
1
Deul, Maurice
1
Diamond, W. P.
1
Fisher, Donald W., 1922-2012,
1
Forbes, John J. V. 1885-1975
1
Galek, James A.
1
Grant, U. S. 1867-1932
1
Greenwald, H. P. 1893-
1
Griffith, Walter R.
1
Griffith, William, 1855-
1
Grove, G. W. 1887-
1
Hartmann, Irving, 1905-
1
Hoffman, John N.
1
Holcomb, J. W.
1
Holmes, J. A. 1859-1915
1
Iannacchione, Anthony
1
Iannacchione, Anthony T.
1
Knopf, Adolph, 1882-1966
1
Kohl, William R.
1
Martin, Lawrence, 1880-1955
1
Martin, Lawrence, 1880-1955,
1
Matetic, Rudy J.
1
Michrina, Barry P. 1947-
1
Moebs, Noel N.
1
Moffit, Fred H. 1874-1958?
1
Nickles, John M. 1859-1945
1
Pennsylvania. Bureau of Topographic and Geologic Survey
1
Pennsylvania. Bureau of Topographic and Geologic Survey,
1
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