Siti Norsaffirah Zailan, et al. “Magnetite (Fe3O4)-Activated Carbon Composite from Ground Coffee Waste for the Removal of Copper Ions (Cu2+) from Solution”. International Journal of Nanoelectronics and Materials (IJNeaM) , vol. 17, no. December, Dec. 2024, pp. 147-53, doi:10.58915/ijneam.v17iDecember.1618.