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3Nicholas Griffin: "Denoting Concepts in the Principles of Mathematics", in Bertrand Rus- sell and the Origins of Analytical Philoso- phy, edited by Ray Monk and Anthony Palmer, Thoemmes Press, 1996.
4Bertrand Russell: The Principles of Mathemat ics, London and New York, 2010.
5R. Perkins: "Why 'On Denoting'?" Russell- the Journal of Bertrand Russell Studies 2007.
