Columbia subject headings:
Alaska--History--To 1867.
Soviet Union--Foreign relations--United States.
United States--Foreign relations--Soviet Union.
Harvard subject headings:
Alaska--Annexation to the United States
Soviet Union--Foreign relations--United States.
United States--Foreign relations--Soviet Union.
Princeton subject headings:
Alaska--Annexation to the United States.
Soviet Union--Foreign relations--United States.
United States--Foreign relations--Soviet Union.