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Autodesk User Group International
officially recognized user group. It is an independent, international organization of Autodesk product users, run by users, for users.
http://www.augi.com/
cadgurus.com
a resource center for CAD professionals.
http://www.cadgurus.com/
Catiaworld
independent resource centre for CATIA, CADAM, DELMIA, ENOVIA, and SMARTEAM users worldwide.
http://www.catiaworld.com/
Design Automation Cafe
virtual meeting place for the EDA community
http://www.DACafe.com/
Professional AutoCAD Users Group (PAUG)
provides networking and peer support for AutoCAD and related software for Denver, Colorado, Wyoming and Rocky Mountain Front Range.
http://www.paug.org/