1. Aristotle: 1958, Metaphysics, intr. comm. W.D. Ross, Oxford.
2. Bocheński, J. M.: 1961, A History of Formal Logic, University of Notre Dame Press, Notre Dame, IN.
3. Bubner, R.: 1982, ‘Handlung, Sprache, Vernunft’, Frankfurt.
4. De Morgan, A.: 1966, ‘Syllabus of a Proposed System of Logic’, in De Morgan: On the Syllogism and other Logical Writings, P. Heath (ed.), Routledge & Kegan Paul, London, pp. 147–207.
5. Hintikka, J.: 1974, ‘Practical vs. Theoretical Reason — An Ambiguous Legacy’, in Körner, St. (ed.): Practical Reason, Dordrecht, pp. 83–102.