Valter, R. E.; Kampare, R. B.; Valtere, S. P.; Balode, D. E.; Batse, A. E.
Chemistry of Heterocyclic Compounds (New York, NY, United States), 1983 , vol. 19, # 12 p. 1290 - 1292
Khimiya Geterotsiklicheskikh Soedinenii, 1983 , vol. 19, # 12 p. 1635 - 1637

Balode,D.E. et al.
Chemistry of Heterocyclic Compounds (New York, NY, United States), 1978 , vol. 14, p. 1326 - 1328
Khimiya Geterotsiklicheskikh Soedinenii, 1978 , vol. 14, # 12 p. 1632 - 1635

Valter, R. E.; Kampare, R. B.; Valtere, S. P.; Balode, D. E.; Batse, A. E.
Chemistry of Heterocyclic Compounds (New York, NY, United States), 1983 , vol. 19, # 12 p. 1290 - 1292
Khimiya Geterotsiklicheskikh Soedinenii, 1983 , vol. 19, # 12 p. 1635 - 1637