Mohamad A.K.Ahmed, et al. “Surface Roughening of Poly (methyl-Methacrylate) Membranes by SF6-Glow-Discharge Plasma Etching”. Tikrit Journal of Pure Science, vol. 20, no. 2, Feb. 2023, pp. 155-60, doi:10.25130/tjps.v20i2.1174.