Columbia subject headings:
Harvard subject headings:
Jülich (Germany)--History--19th century--Exhibitions.
Jülich (Germany)--History--20th century--Exhibitions.
Opladen (Leverkusen, Germany)--History--19th century--Exhibitions.
Opladen (Leverkusen, Germany)--History--20th century--Exhibitions.
Rhine Province (Germany)--History--19th century--Exhibitions.
Rhine Province (Germany)--History--20th century--Exhibitions.
Princeton subject headings:
Jülich (Germany)--History.
Opladen (Leverkusen, Germany)--History.
Rhineland (Germany)--History.