diff --git a/README.org b/README.org
index ceb47e2..6856423 100644
--- a/README.org
+++ b/README.org
@@ -648,6 +648,10 @@ for technical information.
 #+caption: Window management variables.
 #+name: lst:3rd-window-management
 #+begin_src emacs-lisp -n :results none
+(defvar bug-reference-url-format
+  "https://debbugs.gnu.org/cgi/bugreport.cgi?bug=%s"
+  "Setting this as a file local variable enables `bug-reference-mode'")
+
 (with-eval-after-load 'emacs
   ;; https://www.masteringemacs.org/article/demystifying-emacs-window-manager
   (setopt switch-to-buffer-obey-display-actions t)
@@ -7328,6 +7332,7 @@ Only the [[info:org#Top][Org]] source file shows the local variables footer.
 # Emacs looks for "Local variables:" after the last "newline-formfeed".
 
 # Local Variables:
+# bug-reference-url-format: "https://debbugs.gnu.org/cgi/bugreport.cgi?bug=%s"
 # compile-command: "latexmk -interaction=nonstopmode -lualatex -pvc -shell-escape README.tex"
 # fill-column: 80
 # org-edit-src-content-indentation: 0