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personal/wirth/index.html

@@ -122,7 +122,7 @@ Books&nbsp;&nbsp;<a href="Books.pdf">(list)</a>&nbsp;&nbsp;
   <p class="section1" style="text-indent: -18.0pt; margin-left: 36.0pt">
   <span style="font-size: 10.0pt; font-family: Symbol" lang="EN-US">.<span style="font-style: normal; font-variant: normal; font-weight: normal; font-size: 7.0pt; font-family: Times New Roman">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
   </span></span><span lang="EN-GB">Algorithms and Data Structures (1985) (Oberon 
-  version: August 2004)<span style="color: red"> </span>[<span style="color: blue"><a href="AD.pdf">PDF</a></span><span style="color: red">
+  version: August 2004)<span style="color: red"> </span>[<span style="color: blue"><a href="https://www.inf.ethz.ch/personal/wirth/AD.pdf">PDF</a></span><span style="color: red">
   </span>(1'241 KB)]</span></p>
   <div class="section1" style="text-align: center; margin-left: 0pt; margin-right: 0pt; margin-top: 0pt; margin-bottom: .0001pt" align="center">
     <span lang="EN-US"><hr align="center" size="2" width="100%"></span>