Laporan PPM R024/2020: A Comparative Study Using Ammonium Sulfate And Oxalic Acid As Leaching Agents For Rare Earth Element (REE) Extraction From Local Bauxite, December 2020 Costantine Joannes - Perak Pusat Penyelidikan Mineral, Jabatan Mineral Dan Geosains Malaysia 2020 - 19 p. ill, col, photo 29 cm