Columbia subject headings:
Frost, Robert, 1874-1963--Criticism and interpretation.
Frost, Robert, 1874-1963--Philosophy.
Harvard subject headings:
Dualism in literature.
Frost, Robert, 1874-1963--Criticism and interpretation.
Frost, Robert, 1874-1963--Philosophy.
Princeton subject headings:
Dualism in literature.
Frost, Robert, 1874-1963--Criticism and interpretation.
Frost, Robert, 1874-1963--Philosophy.