diff --git a/Doc/Sdi/apache.xml b/Doc/Sdi/apache.xml
index e4159d8663803c60289ee6a6e805c88e8570d93b..c00f46882355a0a7e1809a9d38b6695679d022a1 100644
--- a/Doc/Sdi/apache.xml
+++ b/Doc/Sdi/apache.xml
@@ -69,9 +69,11 @@
           <orgname>Stackoverflow</orgname>)?</para>
 
           <tip>
-            <para>The command <command>dpkg</command> may be used to browse a
-            given package's file content. One of these files belonging to
-            <package>apache2-doc</package> will give you a clue.</para>
+            <para>The <command
+            xlink:href="https://linux.die.net/man/1/dpkg">dpkg</command>
+            command may be used to browse a given package's file content. One
+            of these files belonging to <package>apache2-doc</package> will
+            give you a clue.</para>
           </tip>
         </listitem>