1. Newest Achievements in Petroleum Chemistry and Petroleum Refining, Vol. 4, State Fuel Technology Press [in Russian], p. 271 (1963).
2. Saprygin and Dobryanskii, Zhurnal Obshchei Khimii,9, No. 14, 1313 (1939).
3. J. Am. Chem. Soc.,54, 1614 (1932).
4. Ibid,61, 2134 (1939).
5. Ibid,62, 1293 (1940).