Njoku, C., and E. C. Okigbo. “Development and Validation of Geo-TAN Instructional Software Package for Teaching Geometry in Senior Secondary School”. UNIZIK Journal of STM Education 3, no. 2 (November 21, 2020): 14–28. Accessed October 23, 2021. https://journals.unizik.edu.ng/index.php/jstme/article/view/503.