1. J.R. Gabriel, D.F. Johnston and M.J.D. Powell, Proc.Roy.Soc./London/A264,503 /1962/.
2. B.G. Wybourne, Phys.Rev. 148. 317. /1966/.
3. W.M, Walsh, J. Jeener and N. Blombergen. Phys.Rev. 139A, 1339 /1965/.
4. T. Rewaj Summaries, Jubelee Conf.on Paramagnetic Resonance, Kazan USRR /1969/.
5. T. Rewaj, Fiz.Tv.Tela 9. 2978 /1968/.