1. V. F. Kitaeva, V. V. Obukhov-Denisov, and N. N. Sobolev, Opt. i Spektr.,12, 2, 178 (1962).
2. V. Lokhte-Khol'tgreven (W. Lochte-Holtgrehwen (editor), Methods of Investigating Plasma [Russian translation], Mir (1971).
3. J. Holtsmark and R. Trumpy, Zs. Phys.,31, 803 (1927).
4. L. I. Grechikhin and M. A. El'yashevich, Zh. Prikl. Spektr.,3, 201 (1966).
5. L. I. Grechikhin, Dokl. Akad. Nauk BSSR,10, 232 (1966).