diff --git a/radicale/auth/pam.py b/radicale/auth/pam.py
index 25e66b19..3194cb59 100644
--- a/radicale/auth/pam.py
+++ b/radicale/auth/pam.py
@@ -2,6 +2,8 @@
 #
 # This file is part of Radicale Server - Calendar Server
 # Copyright © 2011 Henry-Nicolas Tourneur
+# Copyright © 2021-2021 Unrud <unrud@outlook.com>
+# Copyright © 2025-2025 Peter Bieringer <pb@bieringer.de>
 #
 # This library is free software: you can redistribute it and/or modify
 # it under the terms of the GNU General Public License as published by