Columbia subject headings:
Art nouveau (Architecture)--Belgium.
Art nouveau (Architecture)--Europe.
Art nouveau--Belgium.
Art nouveau--Europe.
Harvard subject headings:
Architecture--Belgium--19th century.
Architecture--Belgium--20th century.
Architecture--Europe--19th century.
Architecture--Europe--History--20th century
Art nouveau (Architecture)--Belgium.
Art nouveau (Architecture)--Europe.
Art nouveau--Belgium.
Art nouveau--Europe.
Princeton subject headings:
Art nouveau (Architecture)--Belgium.
Art nouveau (Architecture)--Europe.
Art nouveau--Belgium.
Art nouveau--Europe.