Columbia subject headings:
Harvard subject headings:
Portugal--Foreign relations--20th century
Portugal--Politics and government--1910-1974
Portugal. Ministério dos Negócios Estrangeiros--History--20th century.
Princeton subject headings:
Portugal--Foreign relations--1910-1933.
Portugal--Politics and government--1926-1933.
Portugal. Ministério dos Negócios Estrangeiros--History.