diff --git a/ndiff/docs/ndiff.xml b/ndiff/docs/ndiff.xml
index adf9c7b5f..4726c4113 100644
--- a/ndiff/docs/ndiff.xml
+++ b/ndiff/docs/ndiff.xml
@@ -107,8 +107,10 @@
     Google Summer of Code. Michael designed the program and led the
     discussion of its output formats. He wrote versions of the program
     in Perl and C++, but the summer ended shortly after it was decided
-    to rewrite the program in Python for the sake of Windows (and Zenmap)
-    compatibility. This Python version was written by David Fifield.
+    to rewrite the program in Python for the sake of Windows (and
+    Zenmap) compatibility. This Python version was written by David
+    Fifield.  James Levine <ulink url="http://seclists.org/nmap-hackers/2000/0315.html">released</ulink> a Perl script named Ndiff with
+    similar functionality in 2000.
     </para>
   </refsect1>