1. Esaki, L. and Tsu, R. (1970) Superlattice and negative differential conductivity, IBM J. Res. Develop. 14, 61–65.
2. Weisbuch, C. and Vinter, B. (1991) Quantum semiconductor structures, Academic Press, San Diego.
3. Abeles, B. and Tiedje, T. (1983) Amorphous Semiconductor Superlattices, Phys. Rev. Lett 5 1, 2003-2006.
4. Vateva, E. (1988) Photoinduced effects in disordered materials, in M. Borisov, N. Kirov and A. Vavrek (eds.), Disordered Systems and New materials, World Scientific Publishing, Singapore, pp.226–289.
5. Vateva, E., Nesheva, D., Georgieva, I., Arsova, D., Ionov, R. and Chaushev, G. (1989-1990) Electrical and photoelectrical properties of amorphous multilayers bsed on Selenium, University Ann. Techn. Phys. 26, 95–100.