Columbia subject headings:
Harvard subject headings:
Hamburg (Germany)--Ethnic relations.
Hamburg (Germany)--Social conditions.
Jewish socialists--Germany--History.
Jewish socialists--Poland--History.
Jews--Germany--Hamburg--History.
Princeton subject headings:
Jews, Polish--Biography.
Kohn, Joseph Berkowitz, 1841-1905.
Poland--History--Revolution, 1863-1864.
Politicians--Germany--19th century--Biography.
Sozialdemokratische Partei Deutschlands--Biography.