1. Aberdein, A.: The informal logic of mathematical proof. In: Hersh, R. (ed.) 18 Unconventional Essays about the Nature of Mathematics, Springer, New York (2006)
2. Govier, T.: Problems in Argument Analysis and Evaluation, Foris, Dordrecht (1987)
3. Johnson, R.: The Rise of Informal Logic, Vale, Newport News, VA (1996)
4. Jones, V.: A credo of sorts. In: Dales, H.G., Oliveri, G. (eds.) Truth in Mathematics, Clarendon, Oxford (1998)
5. Kirschner, P.A., Buckingham Shum, S.J., Carr, C.S. (eds.): Visualizing Argumentation: Software Tools for Collaborative and Educational Sense-Making. Springer, London (2003)