1. Realism and anti-realism in mathematics;Balaguer;Philos. Math.,2009
2. Mill, J.S. (2023, March 31). A System of Logic. Available online: http://www.sparknotes.com/philosophy/mill/section1.rhtml.
3. Frege, G. (1953). The Foundations of Arithmetic, Basic Blackwell.
4. Sedley, D. (2010). Plato: Meno and Phaedo, Cambridge University Press. Cambridge Texts in the History of Philosophy.
5. Furth, M. (1964). Jena: Verlag Hermann Pohle, Band I/II, University of California Press.