Columbia subject headings:
Literature and society--United States--History--20th century--Congresses.
Sinclair, Upton, 1878-1968--Criticism and interpretation--Congresses.
Social problems in literature--Congresses.
Harvard subject headings:
Literature and society--United States--History--20th century--Congresses.
Sinclair, Upton, 1878-1968--Criticism and interpretation--Congresses.
Social problems in literature--Congresses.
Princeton subject headings:
Literature and society--United States--History--20th century--Congresses.
Sinclair, Upton, 1878-1968--Criticism and interpretation--Congresses.
Social problems in literature--Congresses.