1. E. Rutherford, Selected Scientific Works (Nauka, Moscow, 1971, 1972), Vols. 1, 2 [in Russian].
2. N. Bohr, Usp. Fiz. Nauk, No. 4, 417 (1923).
3. N. Bohr, Usp. Fiz. Nauk, No. 4, 425 (1936).
4. N. Bohr, Selected Scientific Works (Nauka, Moscow, 1971), vols. 1, 2 [in Russian].
5. I. Tamm, Usp. Fiz. Nauk 80, 191 (1963).