Astuti, Indri, F. Mahatmanti, Moch. Setyadji, and Raden Sudibyo. 2021. “Leaching Time and Nitric Acid Concentration Effect on the Separation of Lanthanum and Neodymium Elements from Neodymium Concentrates”. Indonesian Journal of Chemical Science 10 (1), 15-20. https://journal.unnes.ac.id/sju/ijcs/article/view/46066.