Granik, V. G.; Smetskaya, N. I.; Mukhina, N. A.; Persianova, I. V.; Klimenko, V. G.
Chemistry of Heterocyclic Compounds (New York, NY, United States), 1983 , vol. 19, # 9 p. 1027 - 1030
Khimiya Geterotsiklicheskikh Soedinenii, 1983 , # 9 p. 1279 - 1282