diff --git a/src/gsm/milenage/aes-internal-enc.c b/src/gsm/milenage/aes-internal-enc.c
index 4c00f96..6de9992 100644
--- a/src/gsm/milenage/aes-internal-enc.c
+++ b/src/gsm/milenage/aes-internal-enc.c
@@ -19,6 +19,8 @@
  * Alternatively, this software may be distributed under the terms of BSD
  * license.
  *
+ * SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause
+ *
  * See README and COPYING for more details.
  */