Garridos, C. and Balase, E. A. (2011) “Students’ level of understanding of the basic concept of functions and relations: A conceptual analysis”, The Mindanawan Journal of Mathematics, 2(1), pp. 54–65. Available at: https://journals.msuiit.edu.ph/tmjm/article/view/19 (Accessed: 17 September 2024).