Columbia subject headings:
Udmurtii︠a︡ (Russia)--History--Sources.
Ural Mountains Region (Russia)--History--Revolution, 1917-1921--Sources.
Harvard subject headings:
Udmurtii︠a︡ (Russia)--History--Revolution, 1917-1921--Sources.
Ural Mountains Region (Russia)--History--Sources.
Princeton subject headings:
Communism--Russia (Federation)--Kama River Valley.
Communism--Russia (Federation)--Ural Mountains Region.
Kama River Valley (Russia)--History.
Ural Mountains Region (Russia)--History.