diff --git a/common/openpgp-s2k.c b/common/openpgp-s2k.c
index 2b0ba604b..69de76329 100644
--- a/common/openpgp-s2k.c
+++ b/common/openpgp-s2k.c
@@ -1,67 +1,67 @@
 /* openpgp-s2ks.c - OpenPGP S2K helper functions
  * Copyright (C) 1998, 1999, 2000, 2001, 2002, 2003, 2004,
  *               2005, 2006 Free Software Foundation, Inc.
  * Copyright (C) 2010, 2019 g10 Code GmbH
  *
  * This file is part of GnuPG.
  *
  * This file is free software; you can redistribute it and/or modify
  * it under the terms of either
  *
  *   - the GNU Lesser General Public License as published by the Free
  *     Software Foundation; either version 3 of the License, or (at
  *     your option) any later version.
  *
  * or
  *
  *   - the GNU General Public License as published by the Free
  *     Software Foundation; either version 2 of the License, or (at
  *     your option) any later version.
  *
  * or both in parallel, as here.
  *
  * This file 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 this program; if not, see <https://www.gnu.org/licenses/>.
  */
 
 #include <config.h>
 #include <stdlib.h>
 #include <errno.h>
 #include <ctype.h>
 #include <assert.h>
 
 #include "util.h"
 #include "openpgpdefs.h"
 
 
-/* Pack an s2k iteration count into the form specified in RFC-48800.
+/* Pack an s2k iteration count into the form specified in RFC-4880.
  * If we're in between valid values, round up.  */
 unsigned char
 encode_s2k_iterations (int iterations)
 {
   unsigned char c=0;
   unsigned char result;
   unsigned int count;
 
   if (iterations <= 1024)
     return 0;  /* Command line arg compatibility.  */
 
   if (iterations >= 65011712)
     return 255;
 
   /* Need count to be in the range 16-31 */
   for (count=iterations>>6; count>=32; count>>=1)
     c++;
 
   result = (c<<4)|(count-16);
 
   if (S2K_DECODE_COUNT(result) < iterations)
     result++;
 
   return result;
 }