Berozashvili Y.N. ,     Keldysh L.V. ,     Bagaev V.S. ,     Belousova T.Y. Anisotropy of the Absorption of Polarized Light for Semiconductors in a Strong External Electric Field. IX Intern. Conf. on the Phys. of Semiconductors. Moscow.July 23-29 1968. Proc. , с. P.127   Shotov A.P. ,     Berozashvili Y.N. ,     Keldysh L.V. ,     Vul B.M. ,     Zavaritskaya E.I. ,     Bagaev V.S. About the energy spectrum of the heavily doped GaAs (Об энергетическом спектре сильно легированного арсенида галлия) / Ed.Dunod. Radiative recombination. Simpos. 7-th Intern. Conf. on Physics of Semiconductors, Paris, 1964 , с. P.149-154