diff --git a/libfreefare/freefare.h b/libfreefare/freefare.h
index e516162..3af04f7 100644
--- a/libfreefare/freefare.h
+++ b/libfreefare/freefare.h
@@ -70,6 +70,9 @@ typedef unsigned char MifareClassicBlockNumber;
 typedef enum { MFC_KEY_A, MFC_KEY_B } MifareClassicKeyType;
 typedef unsigned char MifareClassicKey[6];
 
+/* NFC Forum public key */
+extern const MifareClassicKey mifare_classic_nfcforum_public_key_a;
+
 int		 mifare_classic_connect (MifareTag tag);
 int		 mifare_classic_disconnect (MifareTag tag);