1. Asghari, A. (2018). Equivalence: An attempt at a history of the idea. Synthese. https://doi.org/10.1007/s11229-018-1674-2
2. Cable, J. (2013). More equal than others: A view from the grassroots. Philosophy of Mathematics Education Journal, 27 (April). http://socialsciences.exeter.ac.uk/education/research/centres/stem/publications/pmej/pome27/index.html. Accessed 6 Apr 2022
3. Cable, J. (2014). La même chose: How mathematics can explain the thinking of children and the thinking of children can illuminate mathematical philosophy. Science & Education, 23(1), 223–240.
4. Carpenter, T. P., & Franke M. L. (2001). Developing algebraic reasoning in the elementary school: Generalization and proof. In H. Chick, K. Stacey, J. Vincent, & J. Vincent (Eds.), The Future of the Teaching and Learning of Algebra (Proceedings of the 12th ICMI Study Conference, Vol. 1, pp. 155–162). Program Committee of ICMI-12 Study.
5. Freudenthal, H. (1983). Didactical phenomenology of mathematical structures. Reidel.