Albert, M., & Hilkermeier, L. (2004). Observing international relations: Niklas Luhmann and world politics. Routledge.
芝加哥风格引文Albert, Mathias, 与 Lena Hilkermeier. Observing International Relations: Niklas Luhmann and World Politics. London ; New York: Routledge, 2004.
MLA引文Albert, Mathias, 与 Lena Hilkermeier. Observing International Relations: Niklas Luhmann and World Politics. Routledge, 2004.
警告：这些引文格式不一定是100％准确.