E. R. Squibb and Sons, Inc.
Patent: US4173649 A1, 1979 ;

Edwards, M.L.; Ritter, H.W.; Stemerick, D.M.; Stewart, K.T.
Journal of Medicinal Chemistry, 1983 , vol. 26, # 3 p. 431 - 436

Dimmock; Patil
Pharmazie, 1986 , vol. 41, # 4 p. 284 - 284

Dyakov, M. Yu.; Sokolova, T. D.; Peretokin, A. V.; Moskovkin, A. S.; Unkovskii, B. V.
Chemistry of Heterocyclic Compounds (New York, NY, United States), 1991 , vol. 27, # 2 p. 183 - 186
Khimiya Geterotsiklicheskikh Soedinenii, 1991 , # 2 p. 224 - 227