Update README.md

README.md

@@ -91,6 +91,16 @@ Python codes: are provided with a test code, environment requirements.txt file,
 
 ## License
 
+GNU GENERAL PUBLIC LICENSE
+Version 3, 29 June 2007
+
+Copyright (C) 2024 Mohsen Raoufi
+
+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 3 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, see <https://www.gnu.org/licenses/>.
 
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