Returns Turtle:
curl -L -i https://ld.zdb-services.de/data/organisations/DE-1a -H "Accept: text/turtle"
Returns HTML:
curl -L -i https://ld.zdb-services.de/data/organisations/DE-1a -H "Accept: application/rdf+xml;q=0.8,application/n-triples;q=0.9,application/trix;q=0.8,application/ld+json;q=0.8,text/shaclc;q=0.8,application/rdf+thrift,text/turtle;q=0.8,text/rdf+n3;q=0.8,application/rdf+json;q=0.8,application/sparql-results+xml,application/sparql-results+json"