During the last years of the war in Viet Nam millions of counterfit North Viet Nam paper money was dropped  from American bombers, one side of the bill looked real, the reverse side was a propaganda letter to the commies telling them they were going down, and telling the public that there goverment was wasting there lives on a war they could not win, I obtained a sample of this paper money fom a bomb handler in Guam, who was stationed with me in 1972 in the USAF.