United Nations. Statistical Office. (1974). World energy supplies, 1969-1972. United Nations.
芝加哥风格引文United Nations. Statistical Office. World Energy Supplies, 1969-1972. New York: United Nations, 1974.
MLA引文United Nations. Statistical Office. World Energy Supplies, 1969-1972. United Nations, 1974.
警告：这些引文格式不一定是100％准确.