• 111 Geology and Geophysics Library (Leith)
• 83 Map Library (Robinson)
• 15 Wisconsin Historical Society Archives
• 11 Memorial Library
• 10 Wisconsin Historical Society Library
• 4 Steenbock Library
• 1 Verona Shelving Facility

• 53 Journals, Magazines, Newspapers
• 1 Books
• 1 Microforms

• 80 Navigation
• 63 Geology
• 25 Floods
• 21 Harbors
• 17 Coasts
• 12 Groundwater
• 11 Population
• 10 Aquifers
• 10 Reservoir sedimentation
• 10 Statistics
• 8 Census districts
• 7 Housing
• 7 Marine sediments
• 5 Water table
• 4 Hydrology
• 4 Sand
• 4 Sedimentation and deposition
• 3 Administrative and political divisions
• 3 Aeronautical charts
• 3 Alluvial fans
• 3 Cities and towns
• 3 History
• 3 Land use
• 3 Roads
• 3 Water-supply

• 142 Geological Survey (U.S.)
• 32 United States Coast Survey
• 31 Puerto Rico. Department of Natural Resources
• 28 United States. National Ocean Service
• 26 Puerto Rico. Department of Public Works
• 25 Puerto Rico. Department of Industrial Research
• 16 Monroe, Watson Hiner, 1907-1992
• 12 National Ocean Survey
• 11 Briggs, Reginald P., 1929-2009
• 10 Puerto Rico Aqueduct and Sewer Authority
• 9 Puerto Rico. Economic Development Administration
• 9 United States. Bureau of the Census
• 8 Haire, William J
• 8 Pease, Maurice H., Jr., 1922-2012
• 8 U.S. Coast and Geodetic Survey
• 6 Puerto Rico Electric Power Authority
• 6 Puerto Rico. Department of Natural and Environmental Resources
• 6 Rodríguez, Rafael W
• 6 Soler-López, Luis R
• 5 Fields, Fred K
• 5 Glover, Lynn
• 5 Hickenlooper, I. J
• 5 International Institute of Tropical Forestry (Río Piedras, San Juan, P.R.)
• 4 Gould, William A
• 4 Gómez-Gómez, Fernando

• 271 English
• 23 Spanish
• 1 Dutch

• 79 Caribbean Sea
• 20 United States Virgin Islands
• 19 North Atlantic Ocean
• 15 United States
• 14 Ensenada Honda (Culebra, P.R.)
• 6 San Juan
• 6 San Juan (P.R.)
• 6 Yabucoa
• 5 Arroyo
• 5 Puerto Maunabo
• 5 San Juan Bay (P.R.)
• 5 Vieques Island (P.R.)
• 5 Vieques Sound (P.R.)
• 4 Cuba
• 4 El Yunque National Forest
• 4 El Yunque National Forest (P.R.)
• 4 Luquillo Region
• 4 Ponce Region
• 3 Fajardo Region
• 3 Virgin Islands
• 2 Atlantic Ocean
• 2 Bayamon Region
• 2 Haiti
• 2 Hawaii

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