diff --git a/doc/references.rst b/doc/references.rst
index 5a349fa9dd960aa393f8f9d5dfd6f696676317e6..056707406d9e3dbf5d73fe5bc03cdd7f49701cbb 100644
--- a/doc/references.rst
+++ b/doc/references.rst
@@ -1,5 +1,6 @@
-
-.. coding=utf-8
+.. SPDX-FileCopyrightText: Copyright © 2023 Idiap Research Institute <contact@idiap.ch>
+..
+.. SPDX-License-Identifier: GPL-3.0-or-later
 
 ============
  References