Columbia subject headings:
Harvard subject headings:
Ri͡azan' (Russia)--History.
Ri︠a︡zanʹ (R.S.F.S.R.)--History.
Russia (Federation)--History--Revolution, 1917-1921.
Soviet Union--History--Revolution, 1917-1921.
Princeton subject headings:
Ri︠a︡zan' (Russia)--History.
Russia (Federation)--History--Revolution, 1917-1921.