Columbia subject headings:
Crimea (Ukraine)--History.
Ukraine--History--Revolution, 1917-1921.
Harvard subject headings:
Crimea (Ukraine)--History.
Soviet Union--History--Revolution, 1917-1921.
Ukraine--History--Revolution, 1917-1921.
Princeton subject headings:
Crimea (Ukraine)--History.
Soviet Union--History--Revolution, 1917-1921.