Columbia subject headings:
Cuba--History--19th century.
Cuba--History--20th century.
Philippines--History--19th century.
Philippines--History--20th century.
Puerto Rico--History--19th century.
Puerto Rico--History--20th century.
Spain--History--19th century.
Spain--History--20th century.
Harvard subject headings:
Cuba--History--19th century.
Cuba--History--20th century.
Philippines--History--19th century.
Philippines--History--20th century.
Puerto Rico--History--19th century.
Puerto Rico--History--20th century.
Spain--History--19th century.
Spain--History--20th century.
Princeton subject headings:
Cuba--History--19th century.
Cuba--History--20th century.
Philippines--History 19th century.
Philippines--History--20th century.
Puerto Rico--History--19th century.
Puerto Rico--History--20th century.
Spain--History--19th century.
Spain--History--20th century.