Author
Pennsylvania. Bureau of Topographic and Geologic Survey
58
Geological Survey (U.S.)
16
Sevon, William D.
9
Geological Survey of Pennsylvania
8
Geological Society of America
7
Berg, Thomas M.
5
Dodge, Clifford H.
5
Edmunds, William E.
5
Faill, Rodger T.
5
Geological Survey (U.S.). Ground Water Branch
5
Geyer, Alan R.
5
Glover, Albert D.
5
McGlade, William G.
5
Swartz, Frank M. (Frank McKim), 1899-1982
5
Wells, Richard B.
5
Ashley, Geo. H. (George Hall), 1866-
4
Bucek, Milena F.
4
Heyman, Louis
4
MacLachlan, David B.
4
Pennsylvania. Department of Conservation and Natural Resources
4
Stose, George Willis, 1869-1960
4
D'Invilliers, E. V. (Edward Vincent), 1857-1928
3
Decade of North American Geology Project
3
Geological Survey (U.S.). Water Resources Division
3
Gray, Carlyle
3
Hoskins, Donald M.
3
Jonas, Anna I. (Anna Isabel), 1881-
3
Kelley, Dana R.
3
Lesley, J. P. (J. Peter), 1819-1903
3
Lohman, Stanley William, 1907-
3
Lytle, William S.
3
Miller, Benjamin L. (Benjamin LeRoy), 1874-1944
3
Root, Samuel I.
3
Rudwick, M. J. S.
3
Shaffner, Marchant N. (Marchant Nissley), 1897-
3
Sholes, Mark A.
3
Woodrow, Donald L.
3
Alberta Society of Petroleum Geologists
2
American Association of Petroleum Geologists
2
American Museum of Natural History
2
Carswell, Louis D.
2
Chronic, Halka
2
Cleaves, Arthur B. (Arthur Bailey), 1905-1985
2
Crandell, Dwight Raymond, 1923-
2
Darwin, Charles, 1809-1882
2
Ebright, John R.
2
Eyles, N.
2
Fauth, John L.
2
Fettke, Charles R. (Charles Reinhard), 1888-1959
2
Geological Society of America. Annual Meeting
2
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