Columbia subject headings:
Harvard subject headings:
Theater--Belgium--History--19th century--Congresses.
Theater--Belgium--History--20th century--Congresses.
Theater--France--History--19th century--Congresses.
Theater--France--History--20th century--Congresses.
Princeton subject headings:
Theater--Belgium--History--19th century.
Theater--Belgium--History--20th century.
Theater--France--History--19th century.
Theater--France--History--20th century.