diff --git a/source/AUTH b/source/AUTH
index 4f4c09c..bdb80e1 100644
--- a/source/AUTH
+++ b/source/AUTH
@@ -60,6 +60,8 @@ garbage_t.png           qubodup
 garbage_tr.png          qubodup
 green.png               qubodup
 grey.png                qubodup
+gui_back_white.png      Derived from UI pack by Kenney Vleugels (www.kenney.nl) (CC0 license)
+gui_back_yellow.png     Derived from UI pack by Kenney Vleugels (www.kenney.nl) (CC0 license)
 help_controller.png     nicefrog (https://opengameart.org/content/generic-gamepad-template)
 i_check_box_area.png    Poul Sander
 icon.png                Poul Sander