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README.md

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 CGDemo
 ======
 
-CGDemo is a companion of the textbook for L. Ammeraal and K. Zhang, Computer Graphics for Java Programmers,  2nd Edition, Wiley, 2006. Copyright (C) 2006  Janis Schubert, Kang Zhang, Leen Ammeraal 
+CGDemo is a companion of the textbook for L. Ammeraal and K. Zhang, Computer Graphics for Java Programmers,  2nd Edition, Wiley, 2006. Copyright (C) 2006  Janis Schubert, Kang Zhang, Leen Ammeraal.
+
+This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version. 
+
+This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.  
+
+You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA. 
+
+More information please see:
+http://www.utdallas.edu/~kzhang/