1. M. Taramasso, G. Perego and B. Notari, Proc. Fifth Int. Conf. on Zeolites, Naples, L.V.C. Rees Ed., p.40, London Heyden and Sons (1980).
2. M. Taramasso, G. Perego and B. Notari, U.S. Pat 4,410,501(1983).
3. R.M. Barrer, Proc. Sixth Int. Conf. on Zeolites, Reno (USA), A. Bisio and D.H. Olson Ed.s, p.870, Butterworth (1984).
4. D.A. Young, U.S. Pat 3,329,481(1967).
5. Zeolite Molecular Sieves;Breck,1974