1. Aristotle, The Complete Works of Aristotle. The Revised Oxford Translation, vol. 1, Jonathan Barnes (ed.), Princeton/NJ: Princeton University Press, 1984.
2. Burge, T., ‘Truth and Singular Terms’, in K. Lambert (ed.), 1991, pp. 189–204.
3. Buss S.: ‘An Introduction to Proof Theory’. In: Buss, S. (eds) Handbook of Proof Theory, pp. 1–78. Elsevier, Amsterdam-Lausanne-New York-Oxford (1998)
4. Gentzen, G., ‘Untersuchungen über das logische Schliessen’, Math. Zeitschrift 39 (1934-5), 176–210, 405–431.
5. Gumb, R.D., ‘Model Sets in a Nonconstructive Logic of Partial Terms with Definite Descriptions’, in R. Dyckhoff (ed.), Automated Reasoning with Analytic Tableaux and Related Methods, International Conference, TABLEAUX 2000, St. Andrews, Scotland, UK, July 2000, vol. 1847 of Lecture Notes in Artificial Intelligence, Berlin: Springer, 2000, pp. 268–278.