diff --git a/license.txt b/license.txt
index 74b7f4aa996ddc4771900f9b489bbcee414d5817..cfb10f23428e74ddc1f72cc72c20d0b9408adf25 100644
--- a/license.txt
+++ b/license.txt
@@ -103,18 +103,26 @@ Files: matlab/allVL1.m
 Copyright: 2007-2010 Bruno Luong <brunoluong@yahoo.com> 
            2019 Dynare Team
 License: GPL-3+
+Comment: The original author gave authorization to change
+ the license from BSD-2-clause to GPL-3+ and redistribute 
+ it under GPL-3+ with Dynare.
 
 Files: matlab/uperm.m
 Copyright: 2014 Bruno Luong <brunoluong@yahoo.com> 
            2019 Dynare Team
 License: GPL-3+
+Comment: The original author gave authorization to change
+ the license from BSD-2-clause to GPL-3+ and redistribute 
+ it under GPL-3+ with Dynare.
 
 Files: matlab/prodmom.m matlab/bivmom.m
 Copyright: 2008-2015 Raymond Kan <kan@chass.utoronto.ca>
            2019-2020 Dynare Team
 License: GPL-3+
- The author would appreciate acknowledgement of the source by
- citation of the following paper:
+Comment: The author gave authorization to redistribute
+ these functions under GPL-3+ with Dynare and would 
+ appreciate acknowledgement of the source by citation
+ of the following paper:
  Kan, R.: "From moments of sum to moments of product."
  Journal of Multivariate Analysis, 2008, vol. 99, issue 3,
  pages 542-554.
diff --git a/matlab/prodmom_deriv.m b/matlab/prodmom_deriv.m
index 7fb11817d0eede6ffbc1cb9945642ccbee4e5e92..b4cd75f66efbe70e67b9ed1a294263ce8da677f6 100644
--- a/matlab/prodmom_deriv.m
+++ b/matlab/prodmom_deriv.m
@@ -6,6 +6,7 @@ function dy = prodmom_deriv(V,ii,nu,dV,dC)
 % Kan, R.: "From moments of sum to moments of product." Journal of 
 % Multivariate Analysis, 2008, vol. 99, issue 3, pages 542-554.
 % =========================================================================
+% Copyright (C) 2008-2015 Raymond Kan <kan@chass.utoronto.ca>
 % Copyright (C) 2019-2020 Dynare Team
 %
 % This file is part of Dynare.