A novel method: Nickel and cobalt extraction from citric acid leaching solution of nickel laterite ores using oxalate precipitation - Astuti, Widi; Nurjaman, Fajar; Rofiek Mufakhir, Fika; Sumardi, Slamet; Avista, Dira; Cleary Wanta, Kevin; Tri Bayu Murti Petrus, Himawan (Minerals engineering, 2023)