Misyura, A. V.; Polumbrik, O. M.; Markovskii, L. N.
Journal of Organic Chemistry USSR (English Translation), 1989 , vol. 25, # 2.2 p. 381 - 387
Zhurnal Organicheskoi Khimii, 1989 , vol. 25, # 2 p. 424 - 431

Tomilenko, E. I.; Nesterenko, A. M.; Kalinin, V. N.; Staninets, V. I.
Chemistry of Heterocyclic Compounds (New York, NY, United States), 1987 , vol. 23, # 7 p. 806 - 809
Khimiya Geterotsiklicheskikh Soedinenii, 1987 , # 7 p. 981 - 984