Columbia subject headings:
Harvard subject headings:
American drama--20th century--Bio-bibliography.
American drama--20th century--History and criticism
English drama--20th century--Bio-bibliography.
English drama--20th century--History and criticism
Princeton subject headings:
American drama--20th century--Bio-bibliography.
American drama--20th century--History and criticism.
English drama--20th century--Bio-bibliography.
English drama--20th century--History and criticism.