1. R. Schonewille, M. Boissoneault, D. Ducharme, and J. Chenier: 44th Annual Conference of Metallurgists: Nickel and Cobalt 2005, Calgary, Canada, 2005, pp. 479–98.
2. Inco Limited: Moving Towards Sustainability, 2005 Good Neighbours Report on Health, Safety, Environment and Community, Inco Limited, Toronto, Canada, 2005.
3. A. Roine: HSC Chemistry, version 6.12 for Windows, Outokumpu Research Oy, Pori, Finland, 2007.
4. P.G. Thornhill: U.S. Patent 2,813,016, November 12, 1957.
5. A.W. Fletcher and M. Shelef: Unit Process in Hydrometallurgy. Group C: Plant Operating Practice—Economics—General, New York Gordon and Breach Science, New York, NY, 1965, pp. 946–70.