• 71 Map Library (Robinson)
• 59 Geology and Geophysics Library (Leith)
• 1 Memorial Library
• 1 Middleton Shelving Facility
• 1 Wisconsin Historical Society Library

• 134 Maps, Atlases
• 65 Books
• 13 Journals, Magazines, Newspapers
• 1 Photos, Drawings, Prints

• 70 Geology
• 61 Groundwater
• 38 Water table
• 34 Soils
• 33 Drainage
• 12 Geology, Stratigraphic
• 12 Hydrology
• 10 Hydrogeology
• 7 Aquifers
• 6 Maps
• 5 Soil mechanics
• 5 Water quality
• 4 Mines and mineral resources
• 4 Pollution
• 4 Quality
• 4 Water
• 3 Agriculture
• 3 Borings
• 3 Environmental aspects
• 3 Formations (Geology)
• 3 Mathematical models
• 3 Water-supply
• 2 Analysis
• 2 Coasts
• 2 Data processing

• 208 Delaware Geological Survey
• 128 Geological Survey (U.S.)
• 34 Boggess, Durward H
• 33 Delaware. State Highway Department
• 26 Adams, John K., 1820-1878
• 17 Andres, A. Scott
• 12 Davis, Christian F. (Christian France)
• 12 Ramsey, Kelvin W
• 9 Spoljaric, Nenad
• 8 Coskery, O. J
• 8 Delaware. Department of Natural Resources and Environmental Control
• 7 Benson, Richard N
• 7 Maryland Geological Survey
• 6 Schenck, William S
• 5 Groot, Johan J., 1918-2009
• 5 Pickett, Thomas E
• 5 Wang, Lillian T
• 4 Woodruff, Kenneth D
• 3 Booth, James Curtis, 1810-1888
• 3 Denver, J. M
• 3 McLaughlin, Peter P. (Peter Paul), 1962-
• 3 Plank, Margaret O
• 3 Reyes, Betzaida
• 3 Talley, John H
• 2 Baxter, Stefanie J

• 208 English

• 202 Delaware
• 30 Sussex County
• 22 Maryland
• 20 Kent County
• 17 New Jersey
• 12 New Castle County
• 11 Pennsylvania
• 3 Atlantic Coast
• 2 Chester County
• 2 Columbia Aquifer
• 2 Lewes Region
• 2 Milford Region
• 2 Milford Region (Del.)
• 2 Piedmont (U.S. : Region)
• 2 Sussex County (Del.)
• 1 Atlantic Coast (Del.)
• 1 Bethany Beach
• 1 Bombay Hook Region
• 1 Calvert Formation
• 1 Cecilton Region
• 1 Clayton Region
• 1 Clayton Region (Del.)
• 1 Columbia Aquifier
• 1 Cypress Swamp Formation
• 1 Delaware River Estuary

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