Columbia subject headings:
Harvard subject headings:
United States--Foreign relations--Vietnam.
United States--History--1945-
Vietnam War, 1961-1975--United States
Vietnam--Foreign relations--United States.
Vietnam--History--1945-1975.
Princeton subject headings:
United States--Foreign relations--Vietnam.
United States--History--1945-
Vietnam War, 1961-1975--United States.
Vietnam--Foreign relations--United States.
Vietnam--History--1945-1975.