Columbia subject headings:
Harvard subject headings:
Agriculture--Soviet Union--History--Sources.
Collective farms--Soviet Union--History--Sources.
Collectivization of agriculture--Soviet Union--History--Sources.
Communism and agriculture--Soviet Union--History--Sources.
Soviet Union--Economic policy--1928-1932.
Princeton subject headings:
Agriculture--Soviet Union--History--Sources.
Collective farms--Soviet Union--History--Sources.
Collectivization of agriculture--Soviet Union--History--Sources.
Communism and agriculture--Soviet Union--History--Sources.
Soviet Union--Economic policy--1928-1932.