Columbia subject headings:
Europe, Central--Emigration and immigration.
Europe, Eastern--Emigration and immigration.
Poland--Emigration and immigration.
Harvard subject headings:
Europe, Central--Emigration and immigration.
Europe, Eastern--Emigration and immigration.
Poland--Emigration and immigration
Princeton subject headings:
Europe, Central--Emigration and immigration.
Europe, Eastern--Emigration and immigration.
Poland--Emigration and immigration.