Columbia subject headings:
Cologne (Germany)--History--Sources--Catalogs.
Historisches Archiv der Stadt Köln--Catalogs.
Protest movements--Germany--Cologne--History--Sources--Catalogs.
Harvard subject headings:
Cologne (Germany)--History--Sources--Catalogs.
Historisches Archiv der Stadt Köln--Catalogs.
Protest movements--Germany--Cologne--History--Sources--Catalogs.
Princeton subject headings:
Catalogs.
Cologne (Germany)--History--Sources--Catalogs.
Historisches Archiv der Stadt Köln--Catalogs.
Protest movements--Germany--Cologne--History--Sources--Catalogs.