Columbia subject headings:
Harvard subject headings:
Bulgaria--Ethnic relations.
Bulgaria--History--1941-1945.
Holocaust, Jewish (1939-1945)
Jews--Bulgaria--History.
World War, 1939-1945--Bulgaria.
World War, 1939-1945--Jews--Bulgaria.
Princeton subject headings:
Boris III, Czar of Bulgaria, 1894-1943.
Bulgaria--Ethnic relations.
Holocaust, Jewish (1939-1945)
Jews--Bulgaria--History.