Columbia subject headings:
Communism--Soviet Union--Sources.
Labor movement--Soviet Union--Sources.
Saint Petersburg (Russia)--History--20th century--Sources.
Soviet Union--Politics and government--1917-1936--Sources.
Working class--Soviet Union--Sources.
Harvard subject headings:
Communism--Soviet Union--Sources.
Labor movement--Soviet Union--Sources.
Saint Petersburg (Russia)--History--20th century--Sources.
Soviet Union--Politics and government--1917-1936--Sources.
Working class--Soviet Union--Sources.
Princeton subject headings:
Soviet Union--Economic policy--1917-1928--Sources.
Working class--Russia (Federation)--Saint Peterburg--History--Sources.