Columbia subject headings:
Nazi concentration camps--Poland--History--Congresses.
Słońsk (Poland : Concentration camp)--History--Congresses.
Harvard subject headings:
Concentration camps--Poland--History--Congresses.
Słońsk (Poland : Concentration camp)--History--Congresses.
Princeton subject headings:
Nazi concentration camps--Poland--History--Congresses.
Sonnenburg (Concentration camp)--History--Congresses.