1. J. E. Ferguson , Inorganic Chemistry and the Earth, Pergamon, Oxford, 1982
2. Methods and techniques for the selective extraction and recovery of oxoanions
3. H. Stephan , K.Gloe, W.Kraus, H.Spies, B.Johannsen, K.Wichmann, G.Reck, D. K.Chand, P. K.Bharadwaj, U.Müller, W. M.Müller and F.Vögtle, in Anion Separations: Fundamentals and Applications, eds. R. P. Singh and B. A. Moyer, Kluwer, NewYork, 2003, in press
4. Coordination Chemistry of Azacryptands