Columbia subject headings:
Labor movement--Italy--History--20th century.
Leone, Enrico--Political and social views.
Harvard subject headings:
Labor leaders--Italy--Biography.
Labor movement--Italy--History--20th century.
Leone, Enrico--Political and social views.
Socialism--Italy--20th century.
Socialists--Italy--Biography
Syndicalism--Italy--History--20th century.
Working class--Political activity--Italy--History--20th century.
Princeton subject headings:
Labor leaders--Italy--Biography.
Labor movement--Italy--History--20th century.
Leone, Enrico--Political and social views.
Socialism--Italy--History--20th century.
Socialists--Italy--Biography.
Syndicalism--Italy--History--20th century.
Working class--Italy--Political activity--History--20th century.