- Fixed copyright message

diff --git a/library/bignum.c b/library/bignum.c
index 4f5bb43..78e9384 100644
--- a/library/bignum.c
+++ b/library/bignum.c
@@ -2,7 +2,10 @@
  *  Multi-precision integer library
  *
  *  Copyright (C) 2006-2010, Brainspark B.V.
+ *
+ *  This file is part of PolarSSL (http://www.polarssl.org)
  *  Lead Maintainer: Paul Bakker <polarssl_maintainer at polarssl.org>
+ *
  *  All rights reserved.
  *
  *  This program is free software; you can redistribute it and/or modify