Columbia subject headings:
Bureaucracy--United States--History--20th century.
Presidents--United States--History--20th century.
Trade regulation--United States--History--20th century.
Harvard subject headings:
Bureaucracy--United States--History--20th century.
Presidents--United States--History--20th century
Trade regulation--United States--History--20th century.
Princeton subject headings:
Bureaucracy--United States--History--20th century.
Presidents--United States--History--20th century.
Trade regulation--United States--History--20th century.