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README.md

@@ -36,7 +36,7 @@ their discussion areas.
 * Representation of logical systems and their trnaslations via Theory Graphs: #5
 * Serious Games for Maths (based on logic and theory graphs): #1 #3
 * Semantics-Extraction from technical/mathematical documents (and the use of this in
-  [mathematical search engines](http//search.mathweb.org)); #2 
+  [mathematical search engines](http//search.mathweb.org)); #2 #6
 * [Integration of theorem prover libraries](http://kwarc.info/projects/OAF) (in the
   [MathHub System](http://mathhub.info)).
 * Active Dokuments and the integration of semantic services into technical/mathematical