Columbia subject headings:
Art metal-workers--Europe--History--To 1500.
Ironwork, Medieval--Europe--Pictorial works.
Harvard subject headings:
Architectural ironwork--Europe--History.
Grilles--Europe--History.
Ironwork--Europe--History.
Metal-work--Europe--History.
Princeton subject headings:
Architectural ironwork--Europe--History.
Grilles--Europe--History.
Ironwork--Europe--History.
Metal-work--Europe--History.