diff --git a/treeview-tutorial.xml b/treeview-tutorial.xml
index a8c2e94..67788c2 100644
--- a/treeview-tutorial.xml
+++ b/treeview-tutorial.xml
@@ -13,6 +13,12 @@
 
         <surname>Müller</surname>
       </author>
+
+      <author>
+        <firstname>Gergely</firstname>
+
+        <surname>Polonkai</surname>
+      </author>
     </authorgroup>
 
     <abstract>