diff --git a/htroot/RankingSolr_p.html b/htroot/RankingSolr_p.html
index 0f34e98b9..31ef1df87 100644
--- a/htroot/RankingSolr_p.html
+++ b/htroot/RankingSolr_p.html
@@ -24,7 +24,7 @@
         <legend>Boost Function</legend>
         A Boost Function can combine numeric values from the result document to produce a number which is multiplied with the score value from the query result.
         To see all available fields, see the <a href="IndexSchema_p.html">YaCy Solr Schema</a> and look for numeric values (these are names with suffix '_i').
-        To find out which kind of operations are possible, see the <a href="http://wiki.apache.org/solr/FunctionQuery" target="_blank">Solr Function Query</a> documentation.
+        To find out which kind of operations are possible, see the <a href="https://lucene.apache.org/solr/guide/6_6/function-queries.html" target="_blank">Solr Function Query</a> documentation.
         Example: to order by date, use "recip(ms(NOW,last_modified),3.16e-11,1,1)", to order by crawldepth, use "div(100,add(crawldepth_i,1))".
         <dl>
           <dt style="width:260px;margin:0;padding:0;height:1.8em;"><label for="bf" id="bf_label">boost=</label></dt>