Columbia subject headings:
Constitutional history--Puerto Rico.
Puerto Rico--Politics and government--1952-1998.
Harvard subject headings:
Constitutional history--Puerto Rico
Puerto Rico--Politics and government--1952-
Puerto Rico--Relations--United States.
United States--Relations--Puerto Rico.
Princeton subject headings:
Constitutional history--Puerto Rico.
Puerto Rico--Politics and government.
Puerto Rico--Relations--United States.
United States--Relations--Puerto Rico.