diff --git a/lib/sha1.c b/lib/sha1.c
index 00b6f467..cd73c52e 100644
--- a/lib/sha1.c
+++ b/lib/sha1.c
@@ -3,9 +3,12 @@
  *
  *	(c) 2015 CZ.NIC z.s.p.o.
  *
- *	Based on the code from libucw6.4
+ *	Based on the code from libucw-6.4
  *	(c) 2008--2009 Martin Mares <mj@ucw.cz>
  *
+ *	Based on the code from libgcrypt-1.2.3, which is
+ *	(c) 1998, 2001, 2002, 2003 Free Software Foundation, Inc.
+ *
  *	Can be freely distributed and used under the terms of the GNU GPL.
  */
 
diff --git a/lib/sha1.h b/lib/sha1.h
index 862e40fe..cb2a5f14 100644
--- a/lib/sha1.h
+++ b/lib/sha1.h
@@ -3,9 +3,12 @@
  *
  *	(c) 2015 CZ.NIC z.s.p.o.
  *
- *	Based on the code from libucw6.4
+ *	Based on the code from libucw-6.4
  *	(c) 2008--2009 Martin Mares <mj@ucw.cz>
  *
+ *	Based on the code from libgcrypt-1.2.3, which is
+ *	(c) 1998, 2001, 2002, 2003 Free Software Foundation, Inc.
+ *
  *	Can be freely distributed and used under the terms of the GNU GPL.
  */
 
diff --git a/lib/sha1_hmac.c b/lib/sha1_hmac.c
index 6eaabea3..58f0ca20 100644
--- a/lib/sha1_hmac.c
+++ b/lib/sha1_hmac.c
@@ -3,9 +3,12 @@
  *
  *	(c) 2015 CZ.NIC z.s.p.o.
  *
- *	Based on the code from libucw6.4
+ *	Based on the code from libucw-6.4
  *	(c) 2008--2009 Martin Mares <mj@ucw.cz>
  *
+ *	Based on the code from libgcrypt-1.2.3, which is
+ *	(c) 1998, 2001, 2002, 2003 Free Software Foundation, Inc.
+ *
  *	Can be freely distributed and used under the terms of the GNU GPL.
  */