1. A. A. Kaminskii, Laser Crystals [in Russian], Nauka, Moscow (1975).
2. Yu. K. Voron'ko, M. V. Dmitruk, G. V. Maksimova, et al., ?Reduced absorption of the Nd3+ ion in various cases,? Zh. Eksp. Teor. Fiz.,57, No. 1, 117?124 (1969).
3. M. Z. Nesanelis, É. S. Zolotovitskaya, and V. K. Shevchenko, ?Spectrographic determination of neodymium in batch and single crystals of iron-yttrium garnets,? Monokrist. Tekhn., No. 5, 141?144 (1971).
4. J. Kvapil, J. Kvapil, and V. Kubecek, ?Laser properties of Nd-doped YAG grown from melt contained in molybdenum crucibles,? Czech. J. Phys.,B29, No. 11, 1282?1292 (1979).
5. B. Cockayne, ?Nonuniform impurity distribution in YAG single crystals,? Phil. Mag.,12, No. 119, 943?950 (1965).