Daukshas, V. K.; Pyatrauskas, O. Yu.; Udrenaite, E. B.; Gaidyalis, P. G.; Gasperavichene, G. A.
Chemistry of Heterocyclic Compounds (New York, NY, United States), 1984 , vol. 20, # 8 p. 838 - 841
Khimiya Geterotsiklicheskikh Soedinenii, 1984 , vol. 20, # 8 p. 1035 - 1038