Columbia subject headings:
Business cycles--United States--History--20th century.
Capitalism--United States--History--20th century.
Marxian economics.
Profit--United States--History--20th century.
Harvard subject headings:
Business cycles--United States--History--20th century.
Capitalism--United States--History--20th century.
Marxian economics.
Profit--United States--History--20th century.
Princeton subject headings:
Business cycles--United States--History--20th century.
Capitalism--United States--History--20th century.
Marxian economics.
Profit--United States--History--20th century.