Columbia subject headings:
International Workingmen's Association.
Labor--Italy--History.
Socialism--Italy--History.
Working class--Italy--History.
Harvard subject headings:
International Workingmen's Association.
Labor--Italy--History.
Socialism--Italy--History
Working class--Italy--History
Princeton subject headings:
International Workingmen's Association (1864-1876)
Socialism--Italy--History.
Working class--Italy--History.