Orlova, T. I.; Epshtein, S. P.; Bogel'fer, L. Ya.; Tashchi, V. P.; Putsykin, Yu. G.
Chemistry of Heterocyclic Compounds (New York, NY, United States), 1990 , vol. 26, # 7 p. 823 - 827
Khimiya Geterotsiklicheskikh Soedinenii, 1990 , # 7 p. 984 - 989

Orlova, T. I.; Epshtein, S. P.; Bogel'fer, L. Ya.; Tashchi, V. P.; Putsykin, Yu. G.
Chemistry of Heterocyclic Compounds (New York, NY, United States), 1990 , vol. 26, # 7 p. 823 - 827
Khimiya Geterotsiklicheskikh Soedinenii, 1990 , # 7 p. 984 - 989

Orlova, T. I.; Epshtein, S. P.; Bogel'fer, L. Ya.; Tashchi, V. P.; Putsykin, Yu. G.
Chemistry of Heterocyclic Compounds (New York, NY, United States), 1990 , vol. 26, # 7 p. 823 - 827
Khimiya Geterotsiklicheskikh Soedinenii, 1990 , # 7 p. 984 - 989

Wieniawski et al.
Roczniki Chemii, 1958 , vol. 32, p. 545,550
Chem.Abstr., 1959 , p. 1461