Columbia subject headings:
English drama--Irish authors--History and criticism.
Yeats, W. B. (William Butler), 1865-1939.
Harvard subject headings:
English drama--Irish authors--History and criticism
English drama--Irish authors--History and criticism.
Yeats, W. B. (William Butler), 1865-1939
Yeats, W. B. (William Butler), 1865-1939--Dramatic works.
Princeton subject headings: