Khodorovskii, V. Yu.; Pukitis, G. G.; Puplovskii, A. Ya.; Edzhinya, A. S.; Neiland, O. Ya.
Chemistry of Heterocyclic Compounds (New York, NY, United States), 1990 , vol. 26, # 1 p. 114
Khimiya Geterotsiklicheskikh Soedinenii, 1990 , # 1 p. 131 - 132