Benacerraf, P. (1981), 'Frege: The Last Logicist'. In P. French at al., eds., The Foundations of Analytic Philosophy. Midwest Studies in Philosophy VI. Minneapolis, MN: Univ. of Minnesota Press, pp. 17-35.

-------- (1972), 'Mathematical Truth', Journal of Philosophy 70: 661-679.

-------- (1996), 'What Mathematical Truth Could Not Be--I'. In A. Morton and S. Stich, eds., Benacerraf and his Critics. Oxford: Blackwell, pp. 9-59.

-------- (1965), 'What Numbers Could Not Be', Philosophical Review 74: 47-73.

Boolos, G. and Jeffrey, R. (1989), Computability and Logic. 3^rd ed. Cambridge: Cambridge Univ. Press.

Frege, G. (1964), Basic Laws of Arithmetic. Trans. M. Furth. Berkeley, CA: Univ. of California Press.

-------- (1953), Foundations of Arithmetic. 2^nd edn. Trans. J.L. Austin. Evanston, IL: Northwestern Univ. Press, 1953.

Friedman, M. (1992), Kant and the Exact Sciences. Cambridge: Harvard Univ. Press.

Hacking, I. (1979), 'What is Logic?', Journal of Philosophy 86: 285-319.

Hale, B. (1987), Abstract Objects. Oxford: Blackwell.

Hanna, R. (2001), Kant and the Foundations of Analytic Philosophy. Oxford: Clarendon/OUP.

Hazen, A.P. (1999), 'Logic and Analyticity'. In A.C. Varzi, ed., The Nature of Logic. Stanford, CA: CSLI, pp. 79-110.

Kemp Smith, N. (1992), A Commentary on Kant's 'Critique of Pure Reason'. 2^nd ed. Atlantic Highlands, NJ: Humanities Press.

Kitcher, P. (1975), 'Kant and the Foundations of Mathematics', Philosophical Review 84: 23-50.

Kripke, S. (1982), Wittgenstein on Rules and Private Language. Cambridge: Harvard Univ. Press.

Longuenesse, B. (1998), Kant and the Capacity to Judge. Trans. C. Wolfe. Princeton: Princeton Univ. Press.

Parsons, C. (1992), 'Arithmetic and the Categories'. In Posy (1992: 135-158).

--------- (1983), 'Kant's Philosophy of Arithmetic'. In C. Parsons, Mathematics in Philosophy. New York: Cornell Univ. Press, pp. 110-149.

--------- (1967), 'Mathematics, Foundations of'. In P. Edwards, ed., Encyclopedia of Philosophy. Vol. 5. New York: Macmillan, pp. 188-213.

Posy, C., ed. (1992), Kant's Philosophy of Mathematics. Dordrecht: Kluwer.

Potter, M. (2000), Reason's Nearest Kin. Oxford: Oxford Univ. Press.

Quine, W.V.O. (1953), 'On What There Is'. In Quine, From a Logical Point of View. New York: Harper and Row, pp. 1-19.

Russell, B. (1981), 'Mathematics and the Metaphysicians'. In Russell, Mysticism and Logic Totowa, NJ: Barnes and Noble, pp. 59-74.

--------- (1959), My Philosophical Development. London: Allen & Unwin, pp. 14-15.

--------- (1996), Principles of Mathematics. 2^nd ed. New York: W.W. Norton.

Shapiro, S. (1998), 'Induction and Indefinite Extensibility: The Gödel Sentence is True, But Did Someone Change the Subject?', Mind 107: 597-624.

--------- (1997), Philosophy of Mathematics: Structure and Ontology. New York: Oxford Univ. Press.

--------- (2000), Thinking about Mathematics. Oxford: Oxford Univ. Press.

Skolem, T. (1967), 'The foundations of elementary arithmetic established by means of the recursive mode of thought, without the use of apparent variables ranging over infinite domains'. In J. v. Heijenoort, ed., From Frege to Gödel. Cambridge: Harvard Univ. Press, pp. 302-333.

Struik, D. J. (1967), A Concise History of Mathematics. New York: Dover.

Tennant, N. (1997), 'On the Necessary Existence of Numbers', Nous 31: 307-336.

Troelstra, A.S. and Dalen, D. v. (1988), Constructivism in Mathematics: An Introduction. Vol. 1. Amsterdam: North Holland.

Wright, C. (1983), Frege's Conception of Numbers as Objects. Aberdeen: Aberdeen Univ. Press.