Columbia subject headings:
Cossacks--Russia (Federation)--Ri︠a︡zanskai︠a︡ oblastʹ.
Ri︠a︡zanskai︠a︡ oblastʹ (Russia)--History.
Harvard subject headings:
Cossacks--Russia (Federation)--Ri︠a︡zanskai︠a︡ oblastʹ.
Ri︠a︡zanskai︠a︡ oblastʹ (Russia)--History.
Princeton subject headings: