1. R. A. Sawyer and H. B. Vincent, Proceedings of the Sixth Summer Conference on Spectroscopy and Its Applications, New York-London (1939), p. 54.
2. S. L. Mandel'shtam, Introduction to Spectral Analysis [in Russian], GOSTTL, Moscow (1946).
3. V. G. Komar, Zh. Tekh. Fiz.,14, 404 (1944).
4. N. Rakhmatulin, ibid,14, 407 (1944).
5. A. Bener, Phys. Verhande,11, 5152 (1960).