Columbia subject headings:
Art nouveau (Architecture)--Belgium--Brussels.
Harvard subject headings:
Architecture, Modern--19th century--Belgium--Brussels--Guidebooks.
Architecture, Modern--20th century--Belgium--Brussels--Guidebooks.
Architecture--Belgium--Brussels--Guidebooks.
Art nouveau (Architecture)--Belgium--Brussels--Guidebooks.
Brussels (Belgium)--Buildings, structures, etc.--Guidebooks.
Princeton subject headings:
Architecture--Belgium--Brussels--19th century.
Architecture--Belgium--Brussels--20th century.
Art nouveau (Architecture)--Belgium--Brussels.
Brussels (Belgium)--Buildings, structures, etc.