Hafiz, A. U., Muhammad, I., Ibrahim, M.J., Watirahyel, W., and Amina, M. “Spatial Analysis of Distribution of Secondary Schools in Giwa Zone of Kaduna State, Nigeria”. International Journal of Science for Global Sustainability, vol. 2, no. 4, Dec. 2016, p. 11, https://fugus-ijsgs.com.ng/index.php/ijsgs/article/view/223.