Columbia subject headings:
City planning--Austria--Vienna--Exhibitions.
Vienna (Austria)--Buildings, structures, etc.--Designs and plans--Exhibitions.
Harvard subject headings:
City planning--Austria--Vienna--Exhibitions.
Vienna (Austria)--Buildings, structures, etc.--Designs and plans--Exhibitions.
Princeton subject headings:
Architecture, Modern--20th century--Austria--Vienna--Congresses.
City planning--Austria--Vienna--Congresses.