2022. Study the Attenuation Ability of γ-Rays Emitted from Co-60 Radioactive Isotope in PES/CaFe2O4 Composite Shields. Journal of the College of Basic Education. 26, 108 (Mar. 2022), 466–479. DOI:https://doi.org/10.35950/cbej.v26i108.5213.