query: #Dutch municipalities that have one or more public libraries
  SELECT 
  ?municipality 
  ?municipalityLabel
  ?muniIsALabel
  (COUNT(?municipality) AS ?AantalOBVestigingen)  
  (GROUP_CONCAT(DISTINCT ?itemLabel ; separator = " --- ") as ?OBVestigingen)
  
  WHERE { #?itemLabel
    ?item wdt:P31 wd:Q28564. #public library
    ?item wdt:P31 wd:Q11396180. #branch 
    ?item wdt:P17 wd:Q55. #from the Netherlands
    ?item wdt:P131 ?municipality.
    ?municipality p:P31 [ps:P31 ?muniIsA].
    VALUES ?muniIsA {wd:Q2039348} #filter only the value "municipality of the Netherlands" Q2039348
    SERVICE wikibase:label { bd:serviceParam wikibase:language "nl" .
                           ?item rdfs:label ?itemLabel.
                           ?municipality rdfs:label ?municipalityLabel.
                           ?muniIsA rdfs:label ?muniIsALabel.
                           }
  }
  GROUP BY ?municipality ?muniIsALabel ?municipalityLabel
  ORDER BY DESC(?AantalOBVestigingen) 