N. Mabungela, N. David Shooto, F. Mtunzi, and E. Bobby Naidoo, “Binary Adsorption Studies of Toxic Metal Ions of Lead and Copper from Aqueous Solution by Modified Foeniculum vulgaris Seeds (Fennel Seeds)”, ajc, vol. 33, no. 7, pp. 1611–1619, Jun. 2021.