Columbia subject headings:
Afghanistan--Foreign relations--Soviet Union.
Mongolia--Foreign relations--Soviet Union.
Soviet Union--Foreign relations--Afghanistan.
Soviet Union--Foreign relations--Mongolia.
Harvard subject headings:
Afghanistan--Relations--Soviet Union.
Mongolia--Relations--Soviet Union.
Soviet Union--Relations--Afghanistan.
Soviet Union--Relations--Mongolia.
Princeton subject headings:
Afghanistan--Relations--Soviet Union.
Mongolia--Relations--Soviet Union.
Soviet Union--Relations--Afghanistan.
Soviet Union--Relations--Mongolia.