Could you please whitelist the following SPARQL endpoint:
This is a SPARQL endpoint used by the National Library of Greece (NLG), whose authority file is linked from Wikidata through https://www.wikidata.org/wiki/Property:P3348; of course it is the most important authority file in Greek language, and it links to Wikidata. Example query (giving all auth IDs from NLG linking to WD):
PREFIX rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#> PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#> PREFIX rda: <http://rdaregistry.info/Elements/a/datatype/> SELECT * WHERE { ?sub rda:P50094 ?obj . FILTER(REGEX(STR(?sub), "A")) FILTER(REGEX(?obj, "entity\\/Q")) }