Columbia subject headings:
Bukharin, Nikolaĭ, 1888-1938.
Communism--Soviet Union--History.
Lenin, Vladimir Ilʹich, 1870-1924.
Soviet Union--Politics and government.
Trotsky, Leon, 1879-1940.
Harvard subject headings:
Bukharin, Nikolaĭ, 1888-1938.
Communists--Soviet Union--Biography
Lenin, Vladimir Ilʹich, 1870-1924
Soviet Union--Politics and government--1917-1936.
Trotsky, Leon, 1879-1940
Princeton subject headings:
Communists--Soviet Union.
Political atrocities--Soviet Union--History.
Soviet Union--Politics and government--1917-1936.