1. Nekovář, P., V. Vacek, Paper presented at 4th Congress CHISA (Prague 1972).
2. Dinh van Sam, P. Nekovář, V. Vacek, ibid.
3. Nekovář, P., V. Vacek, Paper presented at I. S. E. C., (Lyon 1974).
4. Grigar, K., J. Procházka, J. Landau, Coll. Czech. Chem. Comm.37, 1943 (1972).
5. Skelland, A. H. P., In: Dekker, M. (ed.), Solvent Extraction Revs. (1971).1, 215.