Columbia subject headings:
Düsseldorf (Germany)--History--Sources.
Stift St. Lambertus/St. Marien in Düsseldorf--History--Sources.
Harvard subject headings:
Düsseldorf (Germany)--History--Sources.
Stift St. Lambertus/St. Marien in Düsseldorf--History--Sources.
Princeton subject headings:
Düsseldorf (Germany)--Church history--Sources.
Stift St. Lambertus/St. Marien in Düsseldorf--History--Sources.