1. N. P. Diev and J. V. Karjakin: Journal of Applied Chemistry USSR, 1938, vol. 11, pp. 1112–1122, 1389–1397.
2. N. P. Diev and J. V. Karjakin: Journal of Applied Chemistry USSR, 1939, vol. 12, pp. 188–195, 655–661, 668–673.
3. G. M. Schwab and J. Philinis: Journal ACS, 1947, vol. 69, No. 1, pp. 2588–2596.
4. F. C. Thompson and N. Tilling: Journal Soc. of Chemical Industry, 1924, vol. 43 T, p. 37.
5. V. Tafel: Metall und Erz, 1939, vol. 36, pp. 261–287.