diff --git a/doc/magic_cards_notes.md b/doc/magic_cards_notes.md
index 02ad66746..86a5329a2 100644
--- a/doc/magic_cards_notes.md
+++ b/doc/magic_cards_notes.md
@@ -20,6 +20,7 @@ Useful docs:
   * [MIFARE Classic DirectWrite, UFUID version](#mifare-classic-directwrite-ufuid-version)
   * [MIFARE Classic, other versions](#mifare-classic-other-versions)
   * [MIFARE Classic Gen3 aka APDU](#mifare-classic-gen3-aka-apdu)
+  * [MIFARE Classic Gen4 aka GDM](#mifare-classic-gen4-aka-gdm)
   * [MIFARE Classic Super](#mifare-classic-super)
 - [MIFARE Ultralight](#mifare-ultralight)
   * [MIFARE Ultralight blocks 0..2](#mifare-ultralight-blocks-02)