diff --git a/draft-ymbk-idr-l3-discovery.xml b/draft-ymbk-idr-l3-discovery.xml
index 5d117a6..61fc078 100644
--- a/draft-ymbk-idr-l3-discovery.xml
+++ b/draft-ymbk-idr-l3-discovery.xml
@@ -255,9 +255,9 @@
       session running over one AFI MAY carry encapsulations etc. of
       different AFIs,</t>
       
-      <t>A L3DL extension, <!-- <xref
-      target="I-D.ymbk-idr-l3bdl-ulpc"/>,--> describes the next upper
-      layer L3DL protocol to exchange BGP parameter information.</t>
+      <t>A L3DL extension, <xref target="I-D.ymbk-idr-l3nd-ulpc"/>,
+      describes the next upper layer L3DL protocol to exchange BGP
+      parameter information.</t>
 
       <t>The following is a ladder-style diagram of the L3ND protocol
       exchanges:</t>
@@ -1287,6 +1287,7 @@ Flags (bit):
     <?rfc include="reference.RFC.1122.xml"?>
     <?rfc include="reference.RFC.1982.xml"?>
     <?rfc include="reference.RFC.4760.xml"?>
+    <?rfc include="reference.I-D.ymbk-idr-l3nd-ulpc.xml"?>
     <reference anchor="Clos1" target="https://en.wikipedia.org/wiki/Clos_network/">
       <front>
         <title>Clos Network</title>