Author
Gummere, John, 1784-1845
6
Scull, Nicholas
6
Delaware Division of Highways Location and Environmental Studies Office
5
United States Bureau of Chemistry and Soils
5
Delaware Bureau of Archaeology and Historic Preservation
4
Philadelphia Commission on AIDS
4
United States Federal Highway Administration
4
Association of Research Libraries, Washington, Dc. Office ofManagement Services
3
Aycrigg, Benjamin
3
Bell, William Abraham
3
Cleveland and Pittsburgh Railroad Company
3
Geological Survey of New Jersey
3
Gibson, Robert
3
Leonard Davis Institute of Health Economics
3
Lukens, John
3
Pennsylvania Bureau of Topographic and Geologic Survey
3
Pennsylvania State College School of Agriculture
3
Robinson, Moncure, 1802-1891
3
United States Army Corps of Engineers
3
United States Coast and Geodetic Survey
3
Unknown author
3
Association of Practical Surveyors of West New Jersey
2
Atkinson, C. H. 1906-
2
Baltimore and Ohio Railroad Company
2
Brunner, Edmund de S. 1889-1973
2
Campbell, Henry R.
2
Churchman, George 1730-1814
2
Clemson, Thomas Green, 1807-1888
2
Cook, George Hammell, 1818-1889
2
Custer, Jay F., 1955-
2
Day, I. E.
2
Fernon, Thomas S. 1818-1896
2
Heite, Edward F.
2
Jess, Zachariah
2
Leaming, Aaron 1715-1780
2
Lewisburg, Centre and Spruce Creek Railroad Company
2
Moore, Samuel T. 1855-
2
Morse, H. N. 1887-1977
2
Morton, A. C.
2
North Pennsylvania Railroad Company
2
Philadelphia (Pa.) Councils
2
Philadelphia Bureau of Surveys
2
Philadelphia Chamber of Commerce
2
Philadelphia Hospital and Health Survey Committee
2
Roach, Hannah Benner
2
Rogers, Henry D.
2
Rutherfurd, John, 1760-1840
2
Scull, James
2
Simmons, Charles Shaffer, 1900-
2
Trautwine, John C. 1810-1883
2
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