Rizwan Ahmed Qamar, Asim Mushtaq, Ahmed Ullah, and Zaeem Uddin Ali. “Designing of Underground Coal Gasification Unit”. Journal of Advanced Research in Fluid Mechanics and Thermal Sciences, vol. 71, no. 2, Mar. 2024, pp. 103-3, https://semarakilmu.com.my/journals/index.php/fluid_mechanics_thermal_sciences/article/view/6286.