https://upload.wikimedia.org/wikipedia/commons/3/34/Taetigkeitsbericht_2004.pdf
https://www.wikimedia.de/ueber-uns/transparenz/
https://www.semantic-web-journal.net/content/evidence-large-scale-conceptual-disarray-multi-level-taxonomies-wikidata-1
https://www.ngosource.org/ngos/equivalency-determination-guide