Subagja, R. et al. 2016. Peningkatan Kadar Nikel Dalam Laterit Jenis Limonit Dengan Cara Peletasi, Pemanggangan Reduksi Dan Pemisahan Magnet Campuran Bijih, Batu Bara, Dan Na2SO4 [Upgrading of Nickel Content in The Limonitic Laterite Ores by Pelletizing, Reduction Roasting and Magnetic Separation of The Mixed Ores, Coal and Sodium Sulphate]. Jurnal Metalurgi. 31, 2 (Aug. 2016), 103–115. DOI:https://doi.org/10.14203/metalurgi.v31i2.156.