Sibeldin N.N. ,     Boltaev A.P. ,     Loiko N.N. ,     Rzaev M.M. External electric field effect on energy level positions in a quantum well. 8-th Intern. symp."Nanostructures: Physics and Technology", St.Petersburg, Russia, June 19-23, 2000 , с. P.169-172   Kopaev Y.V. ,     Zasavitskii I.I. ,     Sibeldin N.N. ,     Kornyakov N.V. ,     Boltaev A.P. ,     Loiko N.N. ,     Rzaev M.M. Switching effects and negative capacitance in Si/Ge multiple quantum wells. Intern. sympos. "Nanostructure: Physics and Technology", St.Peterburg, Russia, June 24-28 , 1996 , с. P.416-419