Elina, A. S.; Musatova, I. S.; Titkova, R. M.; Dubinskii, R. A.; Goizman, M. S.
Chemistry of Heterocyclic Compounds (New York, NY, United States), 1980 , vol. 16, p. 861 - 863
Khimiya Geterotsiklicheskikh Soedinenii, 1980 , # 8 p. 1106 - 1108

Kluge, Arthur F.; Maddox, Michael L.
Journal of Heterocyclic Chemistry, 1980 , vol. 17, p. 1107 - 1108