Columbia subject headings:
Harvard subject headings:
Nationalism--Puerto Rico--History--20th century
Puerto Rico--Foreign relations--United States.
Puerto Rico--History
Puerto Rico--History--Autonomy and independence movements.
Puerto Rico--Politics and government--1898-1952.
Puerto Rico--Politics and government--1952-
Puerto Rico--Politics and government--1952-1998.
United States--Foreign relations--Puerto Rico.
Princeton subject headings:
Puerto Rico--Politics and government--1898-1952.
Puerto Rico--Relations--United States.
United States--Relations--Puerto Rico.