Foot, P. (2001). Natural goodness. Clarendon ; Oxford University Press.
芝加哥风格引文Foot, Philippa. Natural Goodness. Oxford : New York: Clarendon ; Oxford University Press, 2001.
MLA引文Foot, Philippa. Natural Goodness. Clarendon ; Oxford University Press, 2001.
警告：这些引文格式不一定是100％准确.