Columbia subject headings:
Labor unions--Russia (Federation)--Volga River Region.
Harvard subject headings:
Labor unions and communism--Russia (Federation)--Volga River Region--History.
Labor unions--Russia (Federation)--Volga River Region--History.
Princeton subject headings:
Labor unions and communism--Russia (Federation)--Volga River Region--History.
Labor unions--Russia (Federation)--Volga River Region--History.