Mulligan, R. W. (1955). Ratio superior and ratio inferior: The historical background. The New scholasticism, 29, 1-32.
芝加哥风格引文Mulligan, Robert W. "Ratio Superior and Ratio Inferior: The Historical Background." The New Scholasticism 29 (1955): 1-32.
MLA引文Mulligan, Robert W. "Ratio Superior and Ratio Inferior: The Historical Background." The New Scholasticism, vol. 29, 1955, pp. 1-32.
警告：这些引文格式不一定是100％准确.