1. Aristotle (1984): The Complete Works of Aristotle. The Revised Oxford Translation, vol.1, ed. by Jonathan Barnes, Princeton/NJ: Princeton University Press.
2. Bencivenga, Ermanno, ed. (1976a): Le Logiche libere, Torino: Boringhieri. Bencivenga, Ermanno (1976b): “Set Theory and Free Logic”, in Journal of Philosophical Logic
5, 1–15.
3. Bencivenga, Ermanno (1978a): “A Semantics for a Weak Free Logic”, in Notre Dame Journal of Formal Logic
19, 646–652.
4. Bencivenga, Ermanno (1978b): “Free Semantics for Indefinite Descriptions”, in Journal of Philosophical Logic
7, 389–405.
5. Bencivenga, Ermanno (1980a): “A Weak Free Logic with the Existence Sign”, in Notre Dame Journal of Formal Logic
21, 572–576.