Wubbels, Gene G.; Halverson, Ann M.; Oxman, Joe D.; Bruyn, Van H. De
Journal of Organic Chemistry, 1985 , vol. 50, # 23 p. 4499 - 4504

Gordeev, E. N.; Buyanov, V. N.; Zhigachev, V. E.
Chemistry of Heterocyclic Compounds (New York, NY, United States), 1992 , vol. 28, # 1 p. 40 - 42
Khimiya Geterotsiklicheskikh Soedinenii, 1992 , # 1 p. 46 - 48

Wubbels, Gene G.; Halverson, Ann M.; Oxman, Joe D.; Bruyn, Van H. De
Journal of Organic Chemistry, 1985 , vol. 50, # 23 p. 4499 - 4504