Columbia subject headings:
Harvard subject headings:
National socialism--Congresses
Romani Genocide, 1939-1945--Congresses.
Romanies--History--20th century--Congresses.
World War, 1939-1945--Atrocities--Congresses
Princeton subject headings:
National socialism.
Romani Genocide, 1939-1945.
Romanies--History--20th century.
World War, 1939-1945--Atrocities.