All sources of Sagui library are already under LGPL-2.1.

CMakeLists.txt

@@ -20,22 +20,21 @@
 #
 # Cross-platform library which helps to develop web servers or frameworks.
 #
-# Copyright (c) 2016-2019 Silvio Clecio <[email protected]>
+# Copyright (C) 2016-2019 Silvio Clecio <[email protected]>
 #
-# This file is part of Sagui library.
-#
-# Sagui library is free software: you can redistribute it and/or modify
-# it under the terms of 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.
+# Sagui library is free software; you can redistribute it and/or
+# modify it under the terms of the GNU Lesser General Public
+# License as published by the Free Software Foundation; either
+# version 2.1 of the License, or (at your option) any later version.
 #
 # Sagui library 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.
+# 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 Lesser General Public License
-# along with Sagui library. If not, see <http:https://www.gnu.org/licenses/>.
+# You should have received a copy of the GNU Lesser General Public
+# License along with Sagui library; if not, write to the Free Software
+# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 #
 
 cmake_minimum_required(VERSION 3.0.2)

README.md

@@ -130,9 +130,7 @@ Starting from the version 1.0.0, Sagui follows the [SemVer](https://semver.org)
 
 # Licensing
 
-Sagui is released under GNU Lesser General Public License v3.0. Check the [LICENSE file](https://github.com/risoflora/libsagui/blob/master/LICENSE) for more details.
-
-[![GNU Lesser General Public License v3.0](https://www.gnu.org/graphics/lgplv3-88x31.png)](https://www.gnu.org/licenses/lgpl-3.0.html)
+Sagui is released under GNU Lesser General Public License v2.1. Check the [LICENSE file](https://github.com/risoflora/libsagui/blob/master/LICENSE) for more details.
 
 # Documentation