diff --git a/pkg.m4 b/pkg.m4
index 29e0881..ec5a70d 100644
--- a/pkg.m4
+++ b/pkg.m4
@@ -1,5 +1,5 @@
 # pkg.m4 - Macros to locate and use pkg-config.   -*- Autoconf -*-
-# serial 12 (pkg-config-0.29.2)
+# serial 13 (pkgconf)
 
 dnl Copyright © 2004 Scott James Remnant <scott@netsplit.com>.
 dnl Copyright © 2012-2015 Dan Nicholson <dbn.lists@gmail.com>
@@ -15,9 +15,7 @@ dnl MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
 dnl General Public License for more details.
 dnl
 dnl You should have received a copy of the GNU General Public License
-dnl along with this program; if not, write to the Free Software
-dnl Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
-dnl 02111-1307, USA.
+dnl along with this program; if not, see <https://www.gnu.org/licenses/>.
 dnl
 dnl As a special exception to the GNU General Public License, if you
 dnl distribute this file as part of a program that contains a