1. Development of a solvent extraction process for the separation of cobalt from nickel;Ritcey;CIM Bull.,1975
2. Solvent extraction in hydrometallurgy;Flett,1983
3. Ando, M., Takahashi, M. and Ogata, T., Separation of cobalt from nickel in NMC process. In: K. Osseo-Assare and J. Miller (Editors), Hydrometallurgy, Research Development and Plant Practice. TMS-AIME, Warrendale, Pa. pp. 463–474.
4. Practical study of a solvent extraction system for separation of cobalt and nickel with 2-ethylhexyphosphonic acid and mono-2-ethylhexyl ester;Komasawa;J. Chem. Eng. Jpn.,1984
5. Cobaltnickel separation by solvent extraction with bis-(2,4,4-trimethylpentyl)-phosphinic acid;Rickelton;Solvent Extr. Ion Exch.,1984