Laporan PPM R023/2020: A Feasibility Study Using Ammonium Sulfate And Oxalic Acid To Produce Rare Earth Oxalate From Local Bauxite, December 2020 Costantine Joannes - Perak Pusat Penyelidikan Mineral, Jabatan Mineral Dan Geosains Malaysia 2020 - 18 p. ill, col, photo 29 cm