Columbia subject headings:
Art--Germany--Aachen--20th century--Exhibitions.
Art--Germany--Aachen--21st century--Exhibitions.
Avant-garde (Aesthetics)--Germany--Aachen--Exhibitions.
Harvard subject headings:
Art--Germany--Aachen--20th century--Exhibitions.
Art--Germany--Aachen--21st century--Exhibitions.
Avant-garde (Aesthetics)--Germany--Aachen--Exhibitions.
Princeton subject headings:
Art--Germany--Aachen--20th century--Exhibitions.
Art--Germany--Aachen--21st century--Exhibitions.
Avant-garde (Aesthetics)--Germany--Aachen--Exhibitions.