1. Aristotle (2001) The basic works of Aristotle. Richard McKeon with an introduction by Reeve CDC (eds). (Originally published by Random House in 1941). New York, NY: The Modern Library
2. Becker O (1957) Das mathematische Denken der Antike. Van den Hoeck and Ruprecht, Göttingen
3. Bell ET (1965) Men of mathematics, vol 1. Penguin Books, Harmondsworth
4. Bell JL (2000) Hermann Weyl on intuition and the continuum. Philosophia Naturalis 8:259–273
5. Bell, J.L. (2005). Continuity and infinitesimals, stanford encyclopedia of philosophy, Accessed Aug 6, 2013: plato.stanford.edu/archives/fall2005/entries/continuity/. Accessed on Aug 7, 2013: http://plato.stanford.edu/entries/continuity/