1. “Tunneling Phenomena in Solids”, Plenum Press New York 1969 (Edited by E. Burnstein and S. Lundqvist).
2. C. B. Duke, “Tunneling in Solids,” Academic Press, New York and London 1969 (Edited by F. Seits, D. Turnbull and H. Ehrenreich).
3. L. Eckertová, phys. stat. sol. 18, 3 (1966).
4. R. M. Hill, Thin Solid Films 1, B9 (1967).
5. S. R. Pollack and J. A. Seitschick in “Applied Solid State Science” vol. 1, Academic Press New York and London 1969 (Edited by R. Wolfe).