a questions about license

[Littlemoon917]

Hi guys，
I noticed that the GNU Lesser General Public License is mentioned in the copyright information in the following files:

• mate-volume-control/status-icon-main.c
• mate-volume-control/applet-main.c
• mate-volume-control/dialog-main.c

 * This program is free software; you can redistribute it and/or
 * modify it under the terms of 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.
 *
 * This program 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
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
 * 02110-1301, USA.
 */

However, the GNU General Public License is described in context paragraphs and other code files, is this a mistake?