query: select ?item ?itemLabel ?CatalogcodePPN ?CC_catalog ?CC_reference_url ?CC_stated_in ?CC_retrieved
  where {
    ?item p:P195 ?st .
    ?st  ps:P195 wd:Q1526131 .
    ?st pq:P2868 wd:Q29188408
    OPTIONAL {?item wdt:P528 ?CatalogcodePPN.}  
    OPTIONAL {?item p:P528 [prov:wasDerivedFrom [pr:P854 ?CC_reference_url]] .} 
    OPTIONAL {?item p:P528 [pq:P972 ?CC_catalog].}   
    OPTIONAL {?item p:P528 [prov:wasDerivedFrom [pr:P248 ?CC_stated_in]] .} 
    OPTIONAL {?item p:P528 [prov:wasDerivedFrom [pr:P813 ?CC_retrieved]] .} 
    SERVICE wikibase:label { bd:serviceParam wikibase:language "nl". }
  } ORDER BY ?itemLabel