Hajnal, P. I. (2019). The G20: Evolution, interrelationships, documentation (Second, revised edition.). Routledge.
芝加哥风格引文Hajnal, Peter I. The G20: Evolution, Interrelationships, Documentation. Second, revised edition. London ; New York, New York: Routledge, 2019.
MLA引文Hajnal, Peter I. The G20: Evolution, Interrelationships, Documentation. Second, revised edition. Routledge, 2019.
警告：这些引文格式不一定是100％准确.