Bala Abdullahi, Nura Mu’az Muhammad, R. K. Al-Dadah, and S. Mahmoud. “Optimum Tilt Angle for Solar Collectors Used in Kano, Nigeria”. Journal of Advanced Research in Fluid Mechanics and Thermal Sciences, vol. 56, no. 1, Mar. 2024, pp. 31-42, https://semarakilmu.com.my/journals/index.php/fluid_mechanics_thermal_sciences/article/view/3078.