For relevant subject headings consult the Library of Congress Subject Headings. The first three sources are available online via Galileo, the Georgia online library of databases covering various subjects. Sources for useful documents are as diverse as the Department of Agriculture, the State Department, and various committees of Congress. Many of these are listed in the Ingram Library Online Catalog. The atlas shelves in the Reference area on the main floor of the Ingram Library contain a good selection of current and historical atlases.
Some atlases use alpha-numeric coordinates.
Others use latitude and longitude to give locations.