Surveying Associations  

   Illinois Professional
           Land Surveyor
           Association
 
   American Congress on
          Surveying & Mapping
 
   National Geodetic Survey

   The Defense Mapping
          Agency

   U.S. Army Corp of
          Engineers

   National Geophysical
          Data Center

   American Land Title
          Association

     Surveying References

   U.S. National Archives &
           Records Administration

   Land Records References

   College & University
          Land Surveying Programs