Columbia subject headings:
Immigrants--History--20th century--Sources.
Russians--Foreign countries--History--20th century--Sources.
Soviet Union--Emigration and immigration--Sources.
Harvard subject headings:
Russia--Emigration and immigration--History--Archival resources.
Russians--Cultural assimilation--Foreign countries.
Russians--Foreign countries--Archival resources.
Russians--Foreign countries--Historiography.
Russians--Foreign countries--History--19th century.
Russians--Foreign countries--History--20th century
Soviet Union--Emigration and immigration--History.
Princeton subject headings: