Staskun, Benjamin; Es, Theodorus van
Journal of the Chemical Society, Perkin Transactions 1: Organic and Bio-Organic Chemistry (1972-1999), 1993 , # 4 p. 511 - 516
Belen'kii, L. I.; Cheskis, M. A.; Zvolinskii, V. P.; Obukhov, A. E.
Chemistry of Heterocyclic Compounds (New York, NY, United States), 1986 , vol. 22, # 6 p. 654 - 663
Khimiya Geterotsiklicheskikh Soedinenii, 1986 , vol. 22, # 6 p. 826 - 836