Columbia subject headings:
Art, Spanish--Collectors and collecting--History--19th century--Congresses.
Art, Spanish--Collectors and collecting--History--20th century--Congresses.
Art--Collectors and collecting--Spain--History--19th century--Congresses.
Art--Collectors and collecting--Spain--History--20th century--Congresses.
Harvard subject headings:
Art, Spanish--Collectors and collecting--History--19th century.
Art, Spanish--Collectors and collecting--History--20th century.
Princeton subject headings:
Art, Spanish--Collectors and collecting--History--19th century--Congresses.
Art, Spanish--Collectors and collecting--History--20th century--Congresses.
Art--Collectors and collecting--Spain--History--19th century--Congresses.
Art--Collectors and collecting--Spain--History--20th century--Congresses.