1. Alexy, Robert. 1989. A Theory of Legal Argumentation (first publ. 1978). Trans. Ruth Adler and Neil MacCormick. Oxford: Clarendon Press.
2. Alexy, Robert. 1997. Bulygins Kritik des Richtigkeitsarguments. In Normative Systems in Legal and Moral Theory. Festschrift for Carlos E. Alchourrón and Eugenio Bulygin, ed. Ernesto Garzón Valdés, Werner Krawietz, Georg Hendrik von Wright, and Ruth Zimmerling, 235–250. Berlin: Duncker & Humblot.
3. Alexy, Robert. 2000. On the Thesis of a Necessary Connection Between Law and Morality: Bulygin’s Critique. Ratio Juris 13: 138–147.
4. Alexy, Robert. 2002. The Argument from Injustice. A Reply to Legal Positivism (first publ. 1978). Trans. Bonnie Litschewski Paulson and Stanley L. Paulson. Oxford: Clarendon Press.
5. Alexy, Robert. 2002. A Theory of Constitutional Rights (first publ. 1985). Trans. Julian Rivers. Oxford: Oxford University Press.