diff --git a/doc/guide/logging.xml b/doc/guide/logging.xml
index 85fd91ffa5..9da1cb114b 100644
--- a/doc/guide/logging.xml
+++ b/doc/guide/logging.xml
@@ -694,9 +694,9 @@ Logging/loggers[0]/output_options[0]/maxver 8 integer (modified)
The message identification. Every message in Kea
has a unique identification, which can be used as an
index into the Kea Messages
+ url="kea-messages.html">Kea Messages
Manual () from which more information can be obtained.