Flayh, Ayser Munner, and Sajida Lafta Ghashim. “The Porosity Effect of Stainless Steel Balls on Forced Convection Pipe Flow”. Al-Nahrain Journal for Engineering Sciences, vol. 22, no. 2, July 2019, pp. 102-8, https://doi.org/10.29194/NJES.22020102.