Poludnenko, V. G.; Didinskaya, O. B.; Pozharskii, A. F.
Chemistry of Heterocyclic Compounds (New York, NY, United States), 1984 , vol. 20, # 4 p. 426 - 430
Khimiya Geterotsiklicheskikh Soedinenii, 1984 , vol. 20, # 4 p. 524 - 528