1. R. A. A. Muzzarelli, R. Rocchetti, G. Marangio,J. Radioanal. Chem., 10 (1972) 17.
2. N. Van De Voorde, K. Peeters, Proc. Symp. Developments in the Management of Low and Intermediate Level Radioactive Wastes, I.A.E.A. Aix-en-Provence, Sept. 1970.
3. W. Lutze, H. W. Levi, Proc. Symp. Ion Exchange in Industry, S.A.C. London. July 1969.
4. R. A. A. Muzzarelli, U.S. Patent 3,635,818, 1972 (Italian priority 1968).
5. R. A. A. Muzzarelli, Natural Chelating Polymers, Pergamon, Oxford, 1973.