Sorokina, R. S.; Rybakova, L. F.; Kalinovskii, I. O.; Beletskaya, I. P. Bulletin of the Academy of Sciences of the USSR, Division of Chemical Science (English Translation), 1985 , vol. 34, # 7 p. 1506 - 1509 Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, 1985 , # 7 p. 1647 - 1649