Columbia subject headings:
Art, German--Germany--North Rhine-Westphalia--19th century--Exhibitions.
Art, German--Germany--North Rhine-Westphalia--20th century--Exhibitions.
North Rhine-Westphalia (Germany)--History--Exhibitions.
Harvard subject headings:
Architecture, Modern--20th century--Germany--North Rhine-Westphalia--Exhibitions.
Architecture--Germany--North Rhine-Westphalia--Exhibitions.
Architecture--Germany--North Rhine-Westphalia--History--20th century--Exhibitions.
Art and state--Germany--North Rhine-Westphalia--History--20th century--Exhibitions.
Art museums--Exhibitions--Germany--North Rhine-Westphalia.
Art museums--Germany--North Rhine-Westphalia--Exhibitions.
Art--Collectors and collecting--Germany--North Rhine-Westphalia--History--20th century--Exhibitions.
Art--Study and teaching--Germany--North Rhine-Westphalia--History--20th century--Exhibitions.
Princeton subject headings:
Art, Modern--19th century--Germany (West)--North Rhine-Westphalia--Exhibitions.
Art, Modern--20th century--Germany (West)--North Rhine-Westphalia--Exhibitions.
North Rhine-Westphalia (Germany)--History--Exhibitions.