1. See for example: Henderson, B. and Imbusch, G.F., Optical Spectroscopy of Inorganic Solids, Chapter 9. Clarendon Press, Oxford, 1989 (and references therein)
2. Binois, M., Leblé, A., Rousseau, J.L. and Fayet, J.C., J. Physique Coll., 34, C9, 1973, 285
3. Mityagin, M.V., Nikitin, S.I., Pominov, A.I., Silkin, N.I. and Stolov, A.L., Fiz. Tverd. Tela, 35, 1993, 2578 (engl. transl.: Phys. Solid State, 35, 1993, 1278)
4. Luminescent Cr3+centres in KZnF3: an investigation of the vibronic effects
5. Schnorr, C., Dissertation, Gießen, 1996