Columbia subject headings:
Sharecroppers--Italy--History--20th century--Congresses.
Sharecroppers--Italy--History--Congresses.
Sharecropping--Italy--History--Congresses.
Harvard subject headings:
Sharecroppers--Italy--History--20th century--Congresses.
Sharecroppers--Italy--History--Congresses.
Sharecropping--Italy--History--Congresses.
Sharecropping--Italy--Siena (Province)--History--20th century.
Siena (Italy : Province)--Rural conditions.
Princeton subject headings:
Sharecropping--Italy--Siena (Province)--History--20th century.
Siena (Italy : Province)--Rural conditions.