George, R. P. (2001). In defense of natural law. Oxford: Oxford University Press.
Trích dẫn kiểu ChicagoGeorge, Robert P. In Defense of Natural Law. Oxford: Oxford University Press, 2001.
MLA引文George, Robert P. In Defense of Natural Law. Oxford: Oxford University Press, 2001.
警告：這些引文格式不一定是100％准確.