1. For a fuller discussion of these effects and their relation to the dielectric tensor see J. F. Dillon, Jr., Physics of Magnetic Garnets, ed. A. Paoletti ( North Holland, Amsterdam, 1978 ) p. 379.
2. P. A. Markovin, R. V. Pisarev, G. A. Smolensky, and P. P. Syrnikov, Solid State Commun. 19 (1976) 185.
3. J. R. Dillon, Jr., J. Appl. Phys. 29 (1958) 539.
4. S. Geller, M. A. Gilleo, Acta Crystallogr. 10 (1957) 239.
5. F. Bertaut, F. Forrat, C. R. Acad. Sci. 141 (1956) 382.