American Geographical Society Library



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AGS Map Classification System

The AGS Map or Atlas call number is made up of the following parts:

  • The prefix (optional). Prefixes indicate form or location, and include RARE, VF (vertical file), OV (oversize).
  • The regional number, e.g.: 893 for Wisconsin
  • The regional number modifier:
    • -a Wall Maps (not used).
    • -b Map Sets or Series.
    • -c Map of a part or section of geographic unit.
    • -d Map or plan of a city.
  • The amplification line (cutter by place) names the section (-c) or city (-d) depicted on the map.
  • Terminal line includes the AGS Classification Subject Divisions and the map situation and or publication date (or map scale for series)

*Maps in series or sets will often have the sheet number as the final line

Some Call Number Examples:

A physical map of France from 1745 filed in the rare room.


A geological map series of France at scale 1:250,000.


A population map of the Paris Region of France,from 1980.
An administrative map of Paris depicting Paris as it was in 1789. The map was published in 1995.

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