Effendi, S., et al. “Influence of Synergistic Tributyl Phosphate and Di-(2-ethylhexyl)phosphoric Acid for Separation of Gadolinium and Samarium by Emulsion Liquid Membrane”. Asian Journal of Chemistry, vol. 35, no. 3, Feb. 2023, pp. 563-8, doi:10.14233/ajchem.2023.26924.