Columbia subject headings:
Alaska--Annexation to the United States.
Alaska--History--To 1867.
Russia--Foreign relations--1801-1917.
Soviet Union--Foreign relations--United States.
United States--Foreign relations--1865-1898.
United States--Foreign relations--Soviet Union.
United States--Foreign relations--To 1865.
Harvard subject headings:
Alaska--Annexation to the United States
Soviet Union--Relations--United States.
United States--Relations--Soviet Union.
Princeton subject headings:
Alaska--History--To 1867.
Russia--Foreign relations--United States.
United States--Foreign relations--Russia.