Columbia subject headings:
English drama--20th century--History and criticism.
Theater and society--Great Britain.
Theater--Great Britain--History--20th century.
Theater--Political aspects.
Working class--Great Britain.
Harvard subject headings:
English drama--20th century--History and criticism
Theater and society--Great Britain.
Theater--Great Britain--History--20th century
Theater--Political aspects.
Working class--Great Britain
Princeton subject headings:
Theater--Great Britain.
Theater--History--20th century.