Columbia subject headings:
Harvard subject headings:
Dictatorship--Portugal--History--20th century.
Police--Portugal--History--20th century.
Polícia Internacional e de Defesa do Estado (Portugal)--History.
Portugal--Politics and government--1933-1974.
Portugal. Direcção-Geral de Segurança--History.
Princeton subject headings:
Dictatorship--Portugal--History--20th century.
Police--Portugal--History--20th century.
Polícia Internacional e de Defesa do Estado (Portugal)--History.
Portugal--Politics and government--1933-1974.
Portugal. Direcção-Geral de Segurança--History.