Columbia subject headings:
United States--Foreign economic relations--Vietnam.
Vietnam War, 1961-1975--Missing in action.
Vietnam--Foreign economic relations--United States.
Vietnam--Politics and government--1975-
Harvard subject headings:
United States--Foreign economic relations--Vietnam.
United States--Foreign relations.
Vietnam War, 1961-1975--Missing in action
Vietnam--Foreign economic relations--United States.
Vietnam--Politics and government--1975-
Princeton subject headings:
United States--Foreign economic relations--Vietnam.
Vietnam War, 1961-1975--Missing in action.
Vietnam--Foreign economic relations--United States.
Vietnam--Politics and government--1975-