diff --git a/chapters/authorization-authentication.adoc b/chapters/authorization-authentication.adoc
index eabe6d06..4dce36eb 100644
--- a/chapters/authorization-authentication.adoc
+++ b/chapters/authorization-authentication.adoc
@@ -1681,6 +1681,7 @@ Mohammed's company can then construct segwit transactions to spend these
 payments, taking advantage of segwit features including lower
 transaction fees.
 
+[[mast]]
 === Merklized Alternative Script Trees (MAST)
 
 Using +OP_IF+, you can authorize multiple different spending conditions,