Columbia subject headings:
Architectural photography--Exhibitions.
Compañía Telefónica Nacional de España--Buildings--Pictorial works--Exhibitions.
Harvard subject headings:
Architectural photography--Exhibitions.
Compañía Telefónica Nacional de España--Buildings--Pictorial works--Exhibitions.
Princeton subject headings:
Architectural photography--Exhibitions.
Compañía Telefónica Nacional de España--Buildings--Pictorial works--Exhibitions.