-should supply the same list of nameservers for the zone as the origin
-server does, and none of this authority information should be
-glueless. All the glue should always give the same addresses.
+should supply the same list of nameservers for the zone, and none of
+this authority information should be glueless. All the glue should
+always give the same addresses.
+
+Origin server's data: The set of nameservers in the origin server's
+version of the zone should be a superset of those in the delegations.