Columbia subject headings:
Harvard subject headings:
Russia--History--Alexander III, 1881-1894.
Russia--History--Nicholas II, 1894-1917.
Soviet Union--History--Revolution, 1917-1921--Causes.
Princeton subject headings:
Russia--History--Alexander III, 1881-1894.
Russia--History--Nicholas II, 1894-1917.
Soviet Union--History--Revolution, 1917-1921.