Columbia subject headings:
Sedov, Lev, 1906-1938.
Soviet Union--Politics and government.
Trotsky, Leon, 1879-1940.
Harvard subject headings:
Sedov, Lev, 1906-1938
Soviet Union--Politics and government
Soviet Union--Politics and government--1917-1936
Trotsky, Leon, 1879-1940
Princeton subject headings: