1. Perlow, G.J., Campbell, L.E., Conroy, L.E., Potzel, W.: Phys. Rev. B7, 4044 (1973)
2. de Waard, H., Perlow, G.J.: Phys. Rev. Lett.24, 566 (1970)
3. Perlow, G.J., Potzel, W., Kash, R.M., de Waard, H.: J. Physique (Paris)35, C6?197 (1974)
4. Alfimenkov, V.P.: Sov. Phys.-JETP15, 713 (1962)
5. Beskrovny, A.I., Lebedev, N.A., Ostanevich, Y.M.: Joint Inst. for Nuclear Research report, Dubna, 1971 (unpublished)