Kropotkin, P. (1924). Ethics: Origin and development. London: Harrap & Co.
芝加哥风格引文Kropotkin, Peter. Ethics: Origin and Development. London: Harrap & Co, 1924.
MLA引文Kropotkin, Peter. Ethics: Origin and Development. London: Harrap & Co, 1924.
警告：这些引文格式不一定是100％准确.