diff --git a/build_tools/gather_sources.py b/build_tools/gather_sources.py
index 3ff32f4..b502472 100644
--- a/build_tools/gather_sources.py
+++ b/build_tools/gather_sources.py
@@ -21,22 +21,38 @@ def apply_license(license, relimit, filename):
 
 def apply_python_license(filename):
   license="""#+
-#   CosmoTool -- A cosmotool box for cosmology -- @FILENAME@
-#   Copyright (C) 2007-2013 Guilhem Lavaux
+# This is CosmoTool (@FILENAME@) -- Copyright (C) Guilhem Lavaux (2007-2013)
 #
-#   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; version 2 of the License.
-# 
+# guilhem.lavaux@gmail.com
 #
-#   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.
+# This software is a computer program whose purpose is to provide a toolbox for cosmological
+# data analysis (e.g. filters, generalized Fourier transforms, power spectra, ...)
+
+# This software is governed by the CeCILL license under French law and
+# abiding by the rules of distribution of free software.  You can  use, 
+# modify and/ or redistribute the software under the terms of the CeCILL
+# license as circulated by CEA, CNRS and INRIA at the following URL
+# "http://www.cecill.info". 
 #
-#   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.
+# As a counterpart to the access to the source code and  rights to copy,
+# modify and redistribute granted by the license, users are provided only
+# with a limited warranty  and the software's author,  the holder of the
+# economic rights,  and the successive licensors  have only  limited
+# liability. 
+#
+# In this respect, the user's attention is drawn to the risks associated
+# with loading,  using,  modifying and/or developing or reproducing the
+# software by the user in light of its specific status of free software,
+# that may mean  that it is complicated to manipulate,  and  that  also
+# therefore means  that it is reserved for developers  and  experienced
+# professionals having in-depth computer knowledge. Users are therefore
+# encouraged to load and test the software's suitability as regards their
+# requirements in conditions enabling the security of their systems and/or 
+# data to be ensured and,  more generally, to use and operate it in the 
+# same conditions as regards security. 
+#
+# The fact that you are presently reading this means that you have had
+# knowledge of the CeCILL license and that you accept its terms.
 #+
 """
    
@@ -47,21 +63,38 @@ def apply_python_license(filename):
 
 def apply_cpp_license(filename):
   license="""/*+
-    CosmoTool -- A cosmotool box for cosmology -- @FILENAME@
-    Copyright (C) 2007-2013 Guilhem Lavaux
+This is CosmoTool (@FILENAME@) -- Copyright (C) Guilhem Lavaux (2007-2013)
 
-    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; version 2 of the License.
+guilhem.lavaux@gmail.com
 
-    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.
+This software is a computer program whose purpose is to provide a toolbox for cosmological
+data analysis (e.g. filters, generalized Fourier transforms, power spectra, ...)
 
-    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.
+This software is governed by the CeCILL license under French law and
+abiding by the rules of distribution of free software.  You can  use, 
+modify and/ or redistribute the software under the terms of the CeCILL
+license as circulated by CEA, CNRS and INRIA at the following URL
+"http://www.cecill.info". 
+
+As a counterpart to the access to the source code and  rights to copy,
+modify and redistribute granted by the license, users are provided only
+with a limited warranty  and the software's author,  the holder of the
+economic rights,  and the successive licensors  have only  limited
+liability. 
+
+In this respect, the user's attention is drawn to the risks associated
+with loading,  using,  modifying and/or developing or reproducing the
+software by the user in light of its specific status of free software,
+that may mean  that it is complicated to manipulate,  and  that  also
+therefore means  that it is reserved for developers  and  experienced
+professionals having in-depth computer knowledge. Users are therefore
+encouraged to load and test the software's suitability as regards their
+requirements in conditions enabling the security of their systems and/or 
+data to be ensured and,  more generally, to use and operate it in the 
+same conditions as regards security. 
+
+The fact that you are presently reading this means that you have had
+knowledge of the CeCILL license and that you accept its terms.
 +*/
 """
   relimit = r'^(?s)/\*\+.*\+\*/'