Columbia subject headings:
Colonies--History--19th century.
Imperialism.
International law--History--19th century.
International law--Italy.
Harvard subject headings:
Colonies (International law)--History--19th century.
International law--History--19th century.
International law--History.
Princeton subject headings:
Colonies--History--19th century.
Imperialism.
International law--History--19th century.
International law--Italy.