1. Aristotle, Prior Analytics.
2. Bourbaki, N., ‘Foundations of Mathematics for the Working Mathematician’, Journal of Symbolic Logic 14 (1949), 1–8.
3. Bury, R. G. (transl.), Sextus Empiricus, Vols. 1 and 2, Cambridge, Mass. 1933.
4. Church, A., Introduction to Mathematical Logic, Princeton 1956.
5. Copi, I., Symbolic Logic (2nd ed.), New York 1965.