Reference may be made to Berolzheimer, System der Rechts- und Wirthschaftsphilosophie, II, §§ 25-27, 29 (World's Legal Philosophies, 115-134, 141-156); Hinrichs, Geschichte der Rechts- und Staatsprincipien seit der Reformation, I, 60-274, II, III, 1-318; Korkunov, General Theory of Law, transl. by Hastings, § 7; Charmont, La renaissance du droit naturel, 10-43.
Hobbes, Leviathan (1651).
Spinoza, Ethica (1674).
----, Tractatus theologico-politicas (1670).
Elwes' translation of the two last in Bohn's Libraries must be used with caution.
Bentham, Principles of Morals and Legislation (1780).
A convenient reprint is published by the Clarendon Press.
----, Theory of Legislation. (Originally published in French, 1820). Translated by Hildreth (1864), and in many editions.
Mill, On Liberty (1859).