Columbia subject headings:
Leone, Enrico--Political and social views.
Liberalism--Italy--History--20th century.
Socialism--Italy--History--20th century.
Harvard subject headings:
Leone, Enrico--Political and social views.
Liberalism--Italy--History--20th century
Liberalism.
Socialism--Italy--20th century.
Socialism.
Princeton subject headings:
Leone, Enrico.
Liberalism.
Marxism.