diff --git a/Doc/Sd1/coreClasses.xml b/Doc/Sd1/coreClasses.xml
index 8164ce7ad27818bae1e15887ad45fe5103bc630e..04a778b5232d79fae7ceb3598e39d4c21f9a04bd 100644
--- a/Doc/Sd1/coreClasses.xml
+++ b/Doc/Sd1/coreClasses.xml
@@ -1151,8 +1151,7 @@ b1.equals(b2): true</programlisting>
             <tip>
               <orderedlist>
                 <listitem>
-                  <para>The <link
-                  xlink:href="https://cscircles.cemc.uwaterloo.ca/java_visualize/">Java
+			<para>The <link xlink:href="https://prog.mi.hdm-stuttgart.de/java_visualize/">Java
                   visualizer</link> may be helpful.</para>
                 </listitem>
 
diff --git a/Doc/Sd1/gettingStarted.xml b/Doc/Sd1/gettingStarted.xml
index 0aa0fc9e0ca88e76c118ffca48cdcad006db3c2d..c8c49f5cce698376286b3571f5af672b3f1c7474 100644
--- a/Doc/Sd1/gettingStarted.xml
+++ b/Doc/Sd1/gettingStarted.xml
@@ -166,7 +166,7 @@
       <title>Java Visualizer</title>
 
       <para><link
-      xlink:href="https://prog.mi.hdm-stuttgart.de/java_visualize/visualize.html">http://prog.mi.hdm-stuttgart.de/java_visualize/visualize.html</link></para>
+      xlink:href="https://prog.mi.hdm-stuttgart.de/java_visualize/">http://prog.mi.hdm-stuttgart.de/java_visualize/</link></para>
 
       <para>Help understanding a <xref linkend="glo_Java"/> program's internal
       memory management: Stack and heap</para>