Oleinik, A. F.; Adamskaya, E. V.; Novitskii, K. Yu. Chemistry of Heterocyclic Compounds (New York, NY, United States), 1982 , vol. 18, # 4 p. 337 - 340 Khimiya Geterotsiklicheskikh Soedinenii, 1982 , vol. 18, # 4 p. 453 - 456