1. Hydrometallurgical process for the separation and recovery of nickel from sulfate heap leach liquor of nickeliferrous laterite ores;Agatzini-Leonardou;Miner. Eng.,2009
2. Alexander, J., Bell, E., Treatment of ores. Canada Patent, 1,193,237, 1970.
3. Sulfation of a Nickeliferous Laterite;Bainbridge;Metall. Trans.,1973
4. Bakker, H.F., Bell, M.C.E., Sridhar, R., Gaseous solubilization of reduced metal values. Canadian Patent, 1,013,576,1977.
5. Fundamental and practical factors in ammonia leaching of nickel and cobalt ores;Caron;J. Met.,1950