REFERENCES
- U.S. Patent 2 866 259, 1958.
- Belgian Patent 611 914, 1962.
- Belgian Patent 612 082, 1962.
- U.S. Patent 3 110 589, 1963.
- E. Fitzer, Plawee Proc., 1955, 56.
- F. A. Kroger, “Some Aspects of the Luminescence of Solids”, p. 110. 1948: New York (Elsevier).
- L. H. Brixner, Ph.D. Thesis, Technische Hochschule, Karlsruhe, 1955.
- A. N. Zelikman and N. N. Gorovits, J. Gen. Chem. (U.S.S.R.), 1951, 21 445; 1954, 24, 1897.