Columbia subject headings:
Architecture--Spain--Madrid--History.
Madrid (Spain)--Buildings, structures, etc.
Madrid (Spain)--Description and travel.
Harvard subject headings:
Architecture--Spain--Madrid--History.
Madrid (Spain)--Buildings, structures, etc.
Madrid (Spain)--Description and travel.
Princeton subject headings:
Architecture--Spain--Madrid--History.
Madrid (Spain)--Buildings, structures, etc.
Madrid (Spain)--Description and travel.