Kharchenko, V. G.; Promonenkov, V. K.; Chalaya, S. N.; Lisina, S. N.
Chemistry of Heterocyclic Compounds (New York, NY, United States), 1983 , vol. 19, # 12 p. 1342
Khimiya Geterotsiklicheskikh Soedinenii, 1983 , vol. 19, # 12 p. 1691 - 1692