diff --git a/matlab/gsa/gsa_plotmatrix.m b/matlab/gsa/gsa_plotmatrix.m
index c50bb8f04925eb4c32fba6a7bd6e7663d421a1f4..42b90a5aa4961678779c4df5f64ce9d40862c3b3 100644
--- a/matlab/gsa/gsa_plotmatrix.m
+++ b/matlab/gsa/gsa_plotmatrix.m
@@ -1,4 +1,24 @@
 function gsa_plotmatrix(type,varargin)
+% function gsa_plotmatrix(type,varargin)
+% extended version of the standard MATLAB plotmatrix 
+
+% Copyright (C) 2011-2011 Dynare Team
+%
+% This file is part of Dynare.
+%
+% Dynare 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.
+%
+% Dynare 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 Dynare.  If not, see <http://www.gnu.org/licenses/>.
+
 global bayestopt_ options_ M_
 
 RootDirectoryName = CheckPath('GSA');