Columbia subject headings:
Book industries and trade--Portugal--History--18th century.
Censorship--Portugal--History--18th century.
Prohibited books--Portugal--History--18th century.
Underground literature--Portugal--History--18th century.
Harvard subject headings:
Book industries and trade--Portugal--18th century.
Portugal--Civilization--18th century.
Prohibited books--Portugal--18th century.
Princeton subject headings: