Muzangwa, Jonatan, and Ugorji I. Ogbonnaya. “Undergraduate Mathematics Education Students’ Visual Representations of Multivariable Functions”. Edumatica : Jurnal Pendidikan Matematika 12, no. 3 (December 31, 2022): 212–221. Accessed April 22, 2026. https://www.online-journal.unja.ac.id/edumatica/article/view/15712.