Columbia subject headings:
Harvard subject headings:
German language--Dialects--Russia (Federation)--Volga River Region--Maps.
Germans--Russia (Federation)--Volga River Region.
Volga River Region (Russia)--History.
Princeton subject headings:
German language--Dialects--Russia (Federation)--Volga River Region--Maps.
Germans--Russia (Federation)--Volga River Region.
Volga River Region (Russia)--History.