Author
Geological Survey (U.S.)
31
Geological Survey (U.S.),
8
Chester County Water Resources Authority
7
Pennsylvania. Bureau of Topographic and Geologic Survey
7
Pomeroy, John S., 1929-
6
Reif, Andrew G.
4
Epstein, Jack Burton, 1935-
3
Field Conference of Pennsylvania Geologists
3
Jonas, Anna I. 1881-1974
3
Pennsylvania. Department of Environmental Resources
3
Denny, Charles Storrow, 1911-
2
Drake, Avery Ala, 1927-
2
Epstein, Anita G., 1937-
2
Graham, Jack Bennett, 1913-
2
Hosterman, John W. 1923-
2
Knopf, Eleanora Frances Bliss, 1883-
2
Loper, Connie A.
2
Richardson, G. B. 1872-1949
2
Schreffler, Curtis L.,
2
Sevon, William D.
2
Sloto, Ronald A.
2
Stose, George Willis, 1869-1960
2
Wetzel, Kim L.
2
Wood, Gordon H. 1919-
2
Appalachian Regional Commission
1
Bailey, James F.
1
Baker, Roger C. 1910-
1
Balsley, J. R.
1
Barker, James L., 1936-
1
Barlow, James A., 1923-2015
1
Barlow, Roger
1
Barnes, Ivan, 1931-1989
1
Bascom, F. 1862-1945
1
Bayley, William Shirley, 1861-1943
1
Beamer, N. H. 1913-
1
Beard, Mark M.
1
Berks County Conservancy
1
Biesecker, James E., 1941-
1
Briggs, Reginald P., 1929-2009
1
Brua, Stan A.
1
Brush, Lucien M.
1
Butts, Charles, 1863-1946
1
Chafetz, Henry
1
Chamberlin, Thomas C. 1843-1928,
1
Chester County (Pa.). Health Department
1
Clapp, Frederick G. 1879-1944
1
Clapp, Frederick G. 1879-1944,
1
Colton, George Willis, 1920-
1
Conger, Randall W.
1
Darton, Nelson Horatio, 1865-1948
1
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