Kaigorodova, L. N.; Levitina, E. S.; Karpeiskaya, E. I.; Klabunovskii, E. I. Bulletin of the Academy of Sciences of the USSR, Division of Chemical Science (English Translation), 1984 , vol. 33, p. 747 - 749 Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, 1984 , # 4 p. 813 - 816