Add RFC 3597.

diff --git a/doc/rfc.rst b/doc/rfc.rst
index fc317fdf4c223cdbd2b0eb0e0aabfe36d4d3c1cf..89dd0aa6fc66a976c807c33163415ea7ce214227 100644 (file)
--- a/doc/rfc.rst
+++ b/doc/rfc.rst
@@ -47,6 +47,9 @@ Core RFCs
 `RFC 3007 <https://tools.ietf.org/html/rfc3007>`_
     Dynamic Updates
 
+`RFC 3597 <https://tools.ietf.org/html/rfc3597>`_
+    Handling of Unknown DNS Resource Record (RR) Types
+
 `RFC 3645 <https://tools.ietf.org/html/rfc3645>`_
     GSS-TSIG.