Columbia subject headings:
Architecture, Industrial--Belgium--Wallonia.
Architecture--Belgium--Wallonia--History--20th century.
Architecture--Belgium--Wallonia--History--21st century.
Harvard subject headings:
Architecture--Belgium--Wallonia--20th century.
Architecture--Belgium--Wallonia--21st century.
Princeton subject headings:
Architecture--Belgium--Wallonia--20th century.
Architecture--Belgium--Wallonia--21st century.