A. A. S. Al-Mahab and R. M. Saeed, “The Level of Conceptual Understanding of Functions and their Transformations and its Relationship with the Productive Motivation among Mathematics Students in the Faculty of Education University of Sana`a”, JEPS, vol. 7, no. 17, pp. 156–172, May 2023, doi: 10.26389/AJSRP.M130223.