1. V. V. Mikho and N. V. Malushin, ZhFKh,37, 1587, 1963.
2. D. Hahn and F. W. Seemann, Zs. f. Phys.,146, 644, 1956.
3. V. S. Fomenko, The Emissive Properties of Elements and Chemical Compounds [in Russian], 1964.
4. L. N. Zakgeim, Electrolytic Capacitors [in Russian], 1963.
5. V. V. Mikho, Proceedings of Conference in the Physics Faculty Dedicated to the 100-th Year of Odessa State University [in Russian], 28, 1965.