Columbia subject headings:
Harvard subject headings:
Arts, German--Spain--History--Congresses.
Arts, Spanish--Germany--History--Congresses.
Germany--Civilization--Congresses.
Germany--Relations--Spain--Congresses.
Spain--Civilization--Congresses.
Spain--Relations--Germany--Congresses.
Princeton subject headings:
Arts, German--Spain--History--Congresses.
Arts, Spanish--Germany--History--Congresses.
Germany--Civilization--Congresses.
Germany--Relations--Spain--Congresses.
Spain--Civilization--Congresses.
Spain--Relations--Germany--Congresses.