Engler, R. (1961). The politics of oil: A study of private power and democratic directions. Macmillan.
芝加哥风格引文Engler, Robert. The Politics of Oil: A Study of Private Power and Democratic Directions. New York: Macmillan, 1961.
MLA引文Engler, Robert. The Politics of Oil: A Study of Private Power and Democratic Directions. Macmillan, 1961.
警告：这些引文格式不一定是100％准确.