1. P. I. Abramenko and V. G. Zhiryakov, Zh. Vses. Khim. Ova. im D. I. Mendeleeva,21, 223–225 (1976).
2. P. I. Abramenko and V. A. Kosobutskii, Khim. Geterotsikl. Soedin., No. 9, 1202–1206 (1976).
3. Inventor's Certificate No. 718011 (1980) (USSR); Otkrytiya, No. 7, 306 (1980).
4. Yu. M. Volevenko, V. A. Litenko, G. V. Khranek, et al., Khim. Geterotsikl. Soedin., No. 11, 1476–1478 (1983).
5. V. I. Dulenko and N. N. Alekseev, Khim. Geterotsikl. Soedin., No. 5, 631–634 (1975).