query: PREFIX wdtp: <http://www.wikidata.org/prop/direct/P518>
  #title: most linked wikis on values of property
  SELECT ?wiki (COUNT( DISTINCT ?value ) as ?count_values) (SUM(?uses_of_value) as ?count_statements) (SAMPLE(?i2) as ?sample_use) (SAMPLE(?value) as ?sample_value)
  WITH
  {
      SELECT ?value (count(*) as ?uses_of_value) (SAMPLE(?i) as ?i2)
      {      ?i wdtp: ?value    }
      GROUP BY ?value
  } as %allvalues
  WHERE
  {
        INCLUDE %allvalues    
        [] schema:about ?value ; schema:isPartOf ?wiki . 
  }
  GROUP BY ?wiki
  ORDER BY DESC(?count_values) ?wiki
  LIMIT 50