U.S. Geological Survey "What is GIS" page:
<URL:http://nsdi.usgs.gov/nsdi/pages/what_is_gis.html>

National Center for Geographic Information and Analysis:
<URL:http://www.ncgia.ucsb.edu/publications.html>

USGS Node of the National Geospatial Data Clearinghouse:
<URL:http://nsdi.usgs.gov/nsdi/>

GIS Lab, U. of Miami, US
<URL:http://umgis.merrick.miami.edu>

GIS Modelling examples
<URL:http://www.coresw.com>

GIS WWW Sites in Europe
<URL:http://www.geo.ed.ac.uk/home/giswww.html>

GIS World Publications and Announcements
<URL:http://www.gisworld.com>
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