1. Cobalt Facts (Wickford, England: Cobalt Development Institute, 1995, 1996).
2. R.P. Das, “Processing of Chromite Mine Overburden for Nickel Extraction,” Proceedings of International Conference on Mining and Metallurgy of Complex Nickel Ores, eds. Fu Chongyue et al. (Beijing, China: International Academic Publishers, 1993), pp. 224–225.
3. R.P. Das et al., “Leaching Behaviour of Copper Converter Slag Obtained Under Different Cooling Conditions,” Tr. Inst. Min. Met., Sec. C, 96 (September 1987), pp. 156–162.
4. S. Anand, R.P. Das, and P.K. Jena, “Sulphuric Acid Leaching of Cu, Ni, Co Matte Obtained from Copper Converter Slag,” Hydrometallurgy, 26 (3) (1991), pp. 379–388.
5. R.P. Das, “Hydro and Electrometallurgy in India—An Overview,” Trans. Indian Inst. Metals (December, 1996), pp. 745–752.