Columbia subject headings:
United States--Foreign relations--1945-1989.
United States--Foreign relations--Vietnam.
Vietnam--Foreign relations--United States.
Vietnam--History--1945-1975.
Harvard subject headings:
United States--Foreign relations--1945-1953.
United States--Foreign relations--1945-1989.
United States--Foreign relations--Vietnam.
Vietnam--Foreign relations--United States.
Vietnam--History--1945-1975.
Princeton subject headings:
United States--Foreign relations--1945-1989.
United States--Foreign relations--Vietnam.
Vietnam--Foreign relations--United States.
Vietnam--History--1945-1975.