Presentation Links

Academic Research

• Google Scholar
• Microsoft Academic Search
• ERIC

Symbols and Icons

• AutoDraw
• AIGA symbols and icons (free use)
• Unicode characters
• The Noun Project (icons)
• ISO safety signs
• Amp-What (Unicode and other character search)

Images

• Library of Congress
• Library of Congress: Free to use/public domain
• Library of Congress: Historic American Engineering Record
• National Park Service: Heritage Documentation Programs
• National Map
• National Map viewer
• Iowa Geographic Map Server
• Internet Archive: Images
• Library of Congress: Classic maps
• Archive.org: Images
• Chronicling America (historic newspaper search)
• Smithsonian Open Access
• British Library (out of copyright)

Data Sources

• USDA aerial mapping
• Census Bureau: American Fact Finder
• Census Bureau: Community facts
• CIA World Factbook
• FRED
• Iowa Data Center
• OECD data
• PubChem (chemicals, hazards, etc.)
• World Bank
• National Historical Geography Information System
• Atlas of Historical Geography of the United States