Columbia subject headings:
Germany--History--1933-1945--Sources.
Germany. Geheime Staatspolizei--History--Sources.
North Rhine-Westphalia (Germany)--History--Sources.
Rhineland (Germany)--History--Sources.
Rhineland-Palatinate (Germany)--History--Sources.
Harvard subject headings:
Germany--History--1933-1945--Sources.
Germany. Geheime Staatspolizei--History--Sources.
North Rhine-Westphalia (Germany)--History--Sources.
Rhineland (Germany)--History--Sources.
Rhineland-Palatinate (Germany)--History--Sources.
Princeton subject headings:
Germany--History--1933-1945--Sources.
Germany. Geheime Staatspolizei--History--Sources.
North Rhine-Westphalia (Germany)--History--20th century--Sources.
Rhineland (Germany)--History--20th century--Sources.
Rhineland-Palatinate (Germany)--History--20th century--Sources.