Shmelev, L. V.; Stopnikova, M. N.; Poponova, R. V.; Kessenikh, A. V. Chemistry of Heterocyclic Compounds (New York, NY, United States)Khimiya Geterotsiklicheskikh Soedinenii, 19851985, vol. 2121, # 33 p. 347 - 354413 - 420 doi: 10.1007/BF00506679