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