Banks, W.P., Coleman, M.J. (1981). Two subjective scales of number. Perception & Psychophysics, 29 (2), 95–105. http://doi.org/10.3758/BF03207272.

Busemeyer, J.R., Diederich, A. (2010). Cognitive Modeling. Thousand Oaks: Sage Publications.

Cummins, D.D., Kintsch, W., Reusser, K., Weimer, R. (1988). The role of understanding in solving word problems. Cognitive Psychology, 20 (4), 405–438. http://doi.org/10.1016/0010-0285(88)90011-4.

Dehaene, S. (1997). The Number Sense: How the Mind Creates Mathematics. New York: Oxford University Press.

Fodor, J.A. (1983). Modularity of Mind. Cambridge: MIT Press.

Gordon, P. (2004). Numerical cognition without words: evidence from Amazonia. Science, 306, 496–499. http://doi.org/10.1126/science.1094492.

Halbach, V., Horsten, L. (2005). Computational Structuralism. Philosophia Mathematica, 13(2), 174–186.

Henkin, L. (1950). Completeness in the Theory of Types. The Journal of Symbolic Logic, 15 (2), 81–91.

Hudson, T. (1983). Correspondences and Numerical Differences between Disjoint Sets. Child Development, 54 (1), 84–90.

Kaye, R. (2006). Tennenbaum’s Theorem for Models of Arithmetic, 1–13. Retrieved from http://books.google.com/books?hl=en&lr=&id=x1aPcJnz4iYC&oi=fnd&pg=PA66&dq=Tennenbaum’s+Theorem+for+Models+of+Arithmetic&ots=Ad9n0ZH44h&sig=hM2BdCVfonBkOzYc9N_NONm0q9k.

Krysztofiak, W. (2011). Indexed Natural Numbers in Mind: A Formal Model of the Basic Mature Number Competence. Axiomathes.

Krzymiński, S. (1995). Test rysowania zegara. Postępy Psychiatrii i Neurologii, 4(1(2)), 21–30.

Lakoff, G.,Núñez, R. (2000). Where Mathematics Comes From. New York: Basic Books.

LeFevre, J.-A., Sadesky, G.S., Bisanz, J. (1996). Selection of procedures in mental addition: Reassessing the problem size effect in adults. Journal of Experimental Psychology: Learning, Memory, and Cognition, 22(1), 216–230. http://doi.org/10.1037/0278-7393.22.1.216.

Moyer, R., Landauer, T. (1967). Time required for judgements of numerical inequality. Nature, 215.

Peano, G. (1967). The Principles of Arithmetic. W: J. Van Heijenoort (ed.). From Frege to Godel: A Source Book in Mathematical Logic (pp. 83–97). Cambridge, MA: Harvard University Press.

Seron, X., Pesenti, M., Noël, M.P., Deloche, G., Cornet, J.A. (1992). Images of numbers, or “when 98 is upper left and 6 sky blue”. Cognition, 44(1–2), 159–196. http://doi.org/10.1016/0010-0277(92)90053-K.

Skolem, T. (1971). Peano’s Axioms and Models of Arithmetic. W: L.E.J. Brouwer, E. Beth,
A. Heyting (eds.), Studies in Logic and the Foundations of Mathematics. Amsterdam, London: North-Holland Publishing Company.

Sun, R. (2008). Introduction to Computational Cognitive Modeling What is Computational Cognitive Modeling? W: R. Sun (ed.). The Cambridge Handbook of Computation Psychology
(pp. 1–36). Cambridge, New York: Cambridge University Press.

Zdanowski, K., Quinon, P. (2007). The Intended Model of Arithmetic: An Argument from Tennenbaum’s Theorem. Computation and Logic in the Real World.