1. A.M. Gaudin, Flotation, Chap. 1, 2nd edn., McGraw-Hill, New York, 1957.
2. N.P. Finkelstein, S.A. Allison, in: M.C. Fuerstenau (Ed.), Flotation, A.M. Gaudin Memorial Volume, Chap. 14, Vol. I, American Institute of Mining and Petroleum Engineers, New York, 1976.
3. N.P. Finkelstein, The activation of sulfite minerals for flotation: a review, Int. J. Miner. Process., 1998, in press.
4. The chemistry of activation of sphalerite—a review;Siva Reddy;Miner. Proc. Extract. Metall. Rev.,1988
5. Activation of zinc sulphide with CuII, CdII and PbII: I. Activation in weakly acidic media