Shmelev, L. V.; Stopnikova, M. N.; Poponova, R. V.; Kessenikh, A. V.
Chemistry of Heterocyclic Compounds (New York, NY, United States), 1985 , vol. 21, # 3 p. 347 - 354
Khimiya Geterotsiklicheskikh Soedinenii, 1985 , vol. 21, # 3 p. 413 - 420