Columbia subject headings:
Harvard subject headings:
Afghanistan--Foreign relations--Soviet Union.
Iran--Foreign relations--Soviet Union.
Soviet Union--Foreign relations--1917-1945.
Soviet Union--Foreign relations--Afghanistan.
Soviet Union--Foreign relations--Iran.
Princeton subject headings:
Afghanistan--Foreign relations--Soviet Union.
Iran--Foreign relations--Soviet Union.
Soviet Union--Foreign relations--1917-1945.
Soviet Union--Foreign relations--Afghanistan.
Soviet Union--Foreign relations--Iran.
Soviet Union--Politics and government--1917-1936.